<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2025 Workiva-->
<!--r:d2857dce-58b9-4ae2-9fbd-feefa4e7775a,g:db42a5e2-ebe0-482f-a46c-385aa05896f1-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://lifx.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:type="simple" xlink:href="lifx-20250930.xsd#CondensedConsolidatedBalanceSheetsParenthetical"/>
  <link:definitionLink xlink:role="http://lifx.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_40f97c96-b54c-4581-8be8-ad5a46b0e554" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_f2b19937-1153-41ff-a75c-b72efde3c5e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_40f97c96-b54c-4581-8be8-ad5a46b0e554" xlink:to="loc_us-gaap_StatementTable_f2b19937-1153-41ff-a75c-b72efde3c5e8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_c1b1d72e-ffb5-4be1-ac27-a4b41c75b23c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_f2b19937-1153-41ff-a75c-b72efde3c5e8" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_c1b1d72e-ffb5-4be1-ac27-a4b41c75b23c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_c1b1d72e-ffb5-4be1-ac27-a4b41c75b23c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_c1b1d72e-ffb5-4be1-ac27-a4b41c75b23c" xlink:to="loc_us-gaap_RelatedPartyDomain_c1b1d72e-ffb5-4be1-ac27-a4b41c75b23c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_dc749f69-c0b4-4c70-8225-1c6fb23cd5fb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_c1b1d72e-ffb5-4be1-ac27-a4b41c75b23c" xlink:to="loc_us-gaap_RelatedPartyDomain_dc749f69-c0b4-4c70-8225-1c6fb23cd5fb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_a1a52e2e-0d3d-4fe4-9e54-4d3dc3551649" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_dc749f69-c0b4-4c70-8225-1c6fb23cd5fb" xlink:to="loc_us-gaap_RelatedPartyMember_a1a52e2e-0d3d-4fe4-9e54-4d3dc3551649" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_174b3580-9a24-40a4-967c-b3358eb2115c" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_f2b19937-1153-41ff-a75c-b72efde3c5e8" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_174b3580-9a24-40a4-967c-b3358eb2115c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_174b3580-9a24-40a4-967c-b3358eb2115c_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_174b3580-9a24-40a4-967c-b3358eb2115c" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_174b3580-9a24-40a4-967c-b3358eb2115c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_8f945790-5988-47a8-83eb-ba716445baa1" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_174b3580-9a24-40a4-967c-b3358eb2115c" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_8f945790-5988-47a8-83eb-ba716445baa1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_ConvertibleNoteInvestmentMember_31e9cb6b-809f-4fb6-a3a1-38a36d394b5c" xlink:href="lifx-20250930.xsd#lifx_ConvertibleNoteInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_8f945790-5988-47a8-83eb-ba716445baa1" xlink:to="loc_lifx_ConvertibleNoteInvestmentMember_31e9cb6b-809f-4fb6-a3a1-38a36d394b5c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RelatedPartyInvestmentMember_678b5946-d08b-4497-805a-78ab8191b61f" xlink:href="lifx-20250930.xsd#lifx_RelatedPartyInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_8f945790-5988-47a8-83eb-ba716445baa1" xlink:to="loc_lifx_RelatedPartyInvestmentMember_678b5946-d08b-4497-805a-78ab8191b61f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RelatedPartyWarrantMember_5f5cc6ac-bdf5-4bb2-9e7e-bacbc7e8dace" xlink:href="lifx-20250930.xsd#lifx_RelatedPartyWarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_8f945790-5988-47a8-83eb-ba716445baa1" xlink:to="loc_lifx_RelatedPartyWarrantMember_5f5cc6ac-bdf5-4bb2-9e7e-bacbc7e8dace" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember_2348942a-cb60-4033-a282-29630899241d" xlink:href="lifx-20250930.xsd#lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_8f945790-5988-47a8-83eb-ba716445baa1" xlink:to="loc_lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember_2348942a-cb60-4033-a282-29630899241d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_68a47896-9a66-41a8-a8a0-0bd58a12732d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_40f97c96-b54c-4581-8be8-ad5a46b0e554" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_68a47896-9a66-41a8-a8a0-0bd58a12732d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_5249ef13-d5fd-4e94-840c-e5e464db5004" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_40f97c96-b54c-4581-8be8-ad5a46b0e554" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_5249ef13-d5fd-4e94-840c-e5e464db5004" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_63c3cf99-7d82-4eae-95e1-0411274ab5d7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_40f97c96-b54c-4581-8be8-ad5a46b0e554" xlink:to="loc_us-gaap_CommonStockSharesIssued_63c3cf99-7d82-4eae-95e1-0411274ab5d7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_bd4b0d54-cfc5-4a33-a4bf-2313e884790e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_40f97c96-b54c-4581-8be8-ad5a46b0e554" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_bd4b0d54-cfc5-4a33-a4bf-2313e884790e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_a7f51829-03c8-4541-b137-884b79e8c640" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_40f97c96-b54c-4581-8be8-ad5a46b0e554" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_a7f51829-03c8-4541-b137-884b79e8c640" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermInvestments_617ef065-ae17-4c84-9cbd-b60bc213a8bd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_40f97c96-b54c-4581-8be8-ad5a46b0e554" xlink:to="loc_us-gaap_LongTermInvestments_617ef065-ae17-4c84-9cbd-b60bc213a8bd" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/CondensedConsolidatedStatementsofOperationsandComprehensiveIncomeLoss" xlink:type="simple" xlink:href="lifx-20250930.xsd#CondensedConsolidatedStatementsofOperationsandComprehensiveIncomeLoss"/>
  <link:definitionLink xlink:role="http://lifx.com/role/CondensedConsolidatedStatementsofOperationsandComprehensiveIncomeLoss" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_a02ccce9-0607-4f95-8775-054c412fb428" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_StatementTable_a02ccce9-0607-4f95-8775-054c412fb428" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_a4f312c8-6fbf-46ba-abd5-cac118ddd055" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_a02ccce9-0607-4f95-8775-054c412fb428" xlink:to="loc_srt_ProductOrServiceAxis_a4f312c8-6fbf-46ba-abd5-cac118ddd055" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_a4f312c8-6fbf-46ba-abd5-cac118ddd055_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_a4f312c8-6fbf-46ba-abd5-cac118ddd055" xlink:to="loc_srt_ProductsAndServicesDomain_a4f312c8-6fbf-46ba-abd5-cac118ddd055_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_ae3b8e2f-78e3-47c0-9b6c-6356fd7bf0a6" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_a4f312c8-6fbf-46ba-abd5-cac118ddd055" xlink:to="loc_srt_ProductsAndServicesDomain_ae3b8e2f-78e3-47c0-9b6c-6356fd7bf0a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubscriptionAndCirculationMember_7eaac7f6-0bb4-423d-86d5-b6218128eb13" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubscriptionAndCirculationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_ae3b8e2f-78e3-47c0-9b6c-6356fd7bf0a6" xlink:to="loc_us-gaap_SubscriptionAndCirculationMember_7eaac7f6-0bb4-423d-86d5-b6218128eb13" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_HardwareMember_92c916da-1f6e-48eb-89a3-5e051a4eeba0" xlink:href="lifx-20250930.xsd#lifx_HardwareMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_ae3b8e2f-78e3-47c0-9b6c-6356fd7bf0a6" xlink:to="loc_lifx_HardwareMember_92c916da-1f6e-48eb-89a3-5e051a4eeba0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductAndServiceOtherMember_6ad2ddd6-a524-4ebe-ab64-16838fab7a34" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductAndServiceOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_ae3b8e2f-78e3-47c0-9b6c-6356fd7bf0a6" xlink:to="loc_us-gaap_ProductAndServiceOtherMember_6ad2ddd6-a524-4ebe-ab64-16838fab7a34" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_a7ff5196-3066-44d0-b1f7-4d5ef59adb88" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_a7ff5196-3066-44d0-b1f7-4d5ef59adb88" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_cffb3d1c-33d8-4435-9abc-a1643808c6ec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_cffb3d1c-33d8-4435-9abc-a1643808c6ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_1dc8c832-672d-4e86-a1d2-044ac6d0f71c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossProfit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_GrossProfit_1dc8c832-672d-4e86-a1d2-044ac6d0f71c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingCostsAndExpensesAbstract_8548dbdb-fbeb-47ca-a44f-f53da6e2375b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingCostsAndExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_OperatingCostsAndExpensesAbstract_8548dbdb-fbeb-47ca-a44f-f53da6e2375b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_9b92019a-4b34-4214-a51c-e50434d106e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ResearchAndDevelopmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingCostsAndExpensesAbstract_8548dbdb-fbeb-47ca-a44f-f53da6e2375b" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_9b92019a-4b34-4214-a51c-e50434d106e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpense_a334cc81-e51d-4e48-a36e-1e1fadaf764b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingCostsAndExpensesAbstract_8548dbdb-fbeb-47ca-a44f-f53da6e2375b" xlink:to="loc_us-gaap_SellingAndMarketingExpense_a334cc81-e51d-4e48-a36e-1e1fadaf764b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_ad5ca222-9094-4950-9013-eaf1cbcbc5e4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingCostsAndExpensesAbstract_8548dbdb-fbeb-47ca-a44f-f53da6e2375b" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_ad5ca222-9094-4950-9013-eaf1cbcbc5e4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingCostsAndExpenses_f9db7beb-1f94-4a6b-9f0f-42ff0e52e03b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingCostsAndExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingCostsAndExpensesAbstract_8548dbdb-fbeb-47ca-a44f-f53da6e2375b" xlink:to="loc_us-gaap_OperatingCostsAndExpenses_f9db7beb-1f94-4a6b-9f0f-42ff0e52e03b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_47124052-fe9b-4dbc-8f76-4b7cc756db51" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_OperatingIncomeLoss_47124052-fe9b-4dbc-8f76-4b7cc756db51" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpenseAbstract_29792e00-51c1-447b-b7e4-4984f1e1f34d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonoperatingIncomeExpenseAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_NonoperatingIncomeExpenseAbstract_29792e00-51c1-447b-b7e4-4984f1e1f34d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_FairValueAdjustmentOfConvertibleNotes_b08b8884-05f8-41fa-81b6-da50642fa58d" xlink:href="lifx-20250930.xsd#lifx_FairValueAdjustmentOfConvertibleNotes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_29792e00-51c1-447b-b7e4-4984f1e1f34d" xlink:to="loc_lifx_FairValueAdjustmentOfConvertibleNotes_b08b8884-05f8-41fa-81b6-da50642fa58d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_4af300fb-9d45-4794-9e4c-bb51bb73fe19" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_29792e00-51c1-447b-b7e4-4984f1e1f34d" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_4af300fb-9d45-4794-9e4c-bb51bb73fe19" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_6203332a-6134-40f6-a26e-9228fd3041f2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_29792e00-51c1-447b-b7e4-4984f1e1f34d" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_6203332a-6134-40f6-a26e-9228fd3041f2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfDerivatives_5b44adca-77e7-4ad6-930d-7019ddf25963" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainLossOnSaleOfDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_29792e00-51c1-447b-b7e4-4984f1e1f34d" xlink:to="loc_us-gaap_GainLossOnSaleOfDerivatives_5b44adca-77e7-4ad6-930d-7019ddf25963" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_02da7437-5298-4901-a9c3-ac3f95f686fc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_29792e00-51c1-447b-b7e4-4984f1e1f34d" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_02da7437-5298-4901-a9c3-ac3f95f686fc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_d3e0fa82-af5d-4329-a28b-5cb72fb7471d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeExpenseNonoperatingNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_29792e00-51c1-447b-b7e4-4984f1e1f34d" xlink:to="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_d3e0fa82-af5d-4329-a28b-5cb72fb7471d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_4d1ea26d-6483-4786-813f-0e64e3a2adc0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_29792e00-51c1-447b-b7e4-4984f1e1f34d" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_4d1ea26d-6483-4786-813f-0e64e3a2adc0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_453c8e5b-a386-4a13-b749-2e460b4d06c6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_29792e00-51c1-447b-b7e4-4984f1e1f34d" xlink:to="loc_us-gaap_NonoperatingIncomeExpense_453c8e5b-a386-4a13-b749-2e460b4d06c6" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_04f1f989-e1ae-4f74-b2a7-1900918601cb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_04f1f989-e1ae-4f74-b2a7-1900918601cb" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_dcc5549f-f482-4e96-8c90-c83e31c9a2a1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_dcc5549f-f482-4e96-8c90-c83e31c9a2a1" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_339dd1d0-50da-4687-8093-d3d5283f4b61" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_NetIncomeLoss_339dd1d0-50da-4687-8093-d3d5283f4b61" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_d0861c94-ed58-4ddc-a018-8c9de02042af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_EarningsPerShareBasic_d0861c94-ed58-4ddc-a018-8c9de02042af" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_b4e5cd46-ae57-41f6-979c-eb32bfd33f2c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_EarningsPerShareDiluted_b4e5cd46-ae57-41f6-979c-eb32bfd33f2c" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_8cc9b6c6-0657-4783-a4fd-cf14ac9da650" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_8cc9b6c6-0657-4783-a4fd-cf14ac9da650" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_91c2fcac-711f-4d42-a4da-4b6caf715b4a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_91c2fcac-711f-4d42-a4da-4b6caf715b4a" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_9ce3f637-5cfc-4b52-8708-eb9e6ce1958a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_12e40379-f1d6-4725-840f-8e10bdf8eb18" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_9ce3f637-5cfc-4b52-8708-eb9e6ce1958a" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_d1ed103a-fcb2-4229-9a91-2902d59d43af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_c72d0a03-cfc2-4924-9c01-7a9a38afd1a4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_9ce3f637-5cfc-4b52-8708-eb9e6ce1958a" xlink:to="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_c72d0a03-cfc2-4924-9c01-7a9a38afd1a4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_91e2d016-e745-4235-84c1-e4babc20bdc4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_9ce3f637-5cfc-4b52-8708-eb9e6ce1958a" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTax_91e2d016-e745-4235-84c1-e4babc20bdc4" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/CondensedConsolidatedStatementsofOperationsandComprehensiveIncomeLossParenthetical" xlink:type="simple" xlink:href="lifx-20250930.xsd#CondensedConsolidatedStatementsofOperationsandComprehensiveIncomeLossParenthetical"/>
  <link:definitionLink xlink:role="http://lifx.com/role/CondensedConsolidatedStatementsofOperationsandComprehensiveIncomeLossParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_e4c7fb77-e5b2-4603-9a43-bd6abea348ec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_798abbe9-8cf3-4ca2-9770-52b8758a4872" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_e4c7fb77-e5b2-4603-9a43-bd6abea348ec" xlink:to="loc_us-gaap_StatementTable_798abbe9-8cf3-4ca2-9770-52b8758a4872" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_cd8c26d3-4df7-4a93-be3f-0e72636d48b5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_798abbe9-8cf3-4ca2-9770-52b8758a4872" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_cd8c26d3-4df7-4a93-be3f-0e72636d48b5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_cd8c26d3-4df7-4a93-be3f-0e72636d48b5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_cd8c26d3-4df7-4a93-be3f-0e72636d48b5" xlink:to="loc_us-gaap_RelatedPartyDomain_cd8c26d3-4df7-4a93-be3f-0e72636d48b5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_05b8912f-a36f-4b8b-b235-dd71017e1da5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_cd8c26d3-4df7-4a93-be3f-0e72636d48b5" xlink:to="loc_us-gaap_RelatedPartyDomain_05b8912f-a36f-4b8b-b235-dd71017e1da5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_5e47e4b6-7e22-47d1-98e5-5c6a641e39f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_05b8912f-a36f-4b8b-b235-dd71017e1da5" xlink:to="loc_us-gaap_RelatedPartyMember_5e47e4b6-7e22-47d1-98e5-5c6a641e39f8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_32bc419c-1806-439c-8e06-497258f128f7" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_798abbe9-8cf3-4ca2-9770-52b8758a4872" xlink:to="loc_srt_ProductOrServiceAxis_32bc419c-1806-439c-8e06-497258f128f7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_32bc419c-1806-439c-8e06-497258f128f7_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_32bc419c-1806-439c-8e06-497258f128f7" xlink:to="loc_srt_ProductsAndServicesDomain_32bc419c-1806-439c-8e06-497258f128f7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_61cc15f5-62c8-4901-adc8-12c23fad4e8e" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_32bc419c-1806-439c-8e06-497258f128f7" xlink:to="loc_srt_ProductsAndServicesDomain_61cc15f5-62c8-4901-adc8-12c23fad4e8e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_HardwareMember_69afe337-abad-4189-acf9-d7db50ae9ad5" xlink:href="lifx-20250930.xsd#lifx_HardwareMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_61cc15f5-62c8-4901-adc8-12c23fad4e8e" xlink:to="loc_lifx_HardwareMember_69afe337-abad-4189-acf9-d7db50ae9ad5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductAndServiceOtherMember_30839403-ac82-4d5b-8c2b-bcf53fabb888" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductAndServiceOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_61cc15f5-62c8-4901-adc8-12c23fad4e8e" xlink:to="loc_us-gaap_ProductAndServiceOtherMember_30839403-ac82-4d5b-8c2b-bcf53fabb888" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_a685701b-521e-4969-85cf-7c5d10f3ed73" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e4c7fb77-e5b2-4603-9a43-bd6abea348ec" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_a685701b-521e-4969-85cf-7c5d10f3ed73" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_d2d90c95-e780-49c7-8907-d3d2c5ecf65b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e4c7fb77-e5b2-4603-9a43-bd6abea348ec" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_d2d90c95-e780-49c7-8907-d3d2c5ecf65b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_daed6aa7-c9ee-41cd-a916-cfac630be546" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e4c7fb77-e5b2-4603-9a43-bd6abea348ec" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_daed6aa7-c9ee-41cd-a916-cfac630be546" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_6267db45-95d6-4de6-bb83-6a293b6803b3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e4c7fb77-e5b2-4603-9a43-bd6abea348ec" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_6267db45-95d6-4de6-bb83-6a293b6803b3" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/CondensedConsolidatedStatementsofStockholdersEquity" xlink:type="simple" xlink:href="lifx-20250930.xsd#CondensedConsolidatedStatementsofStockholdersEquity"/>
  <link:definitionLink xlink:role="http://lifx.com/role/CondensedConsolidatedStatementsofStockholdersEquity" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_4c4bd878-94a8-4676-9f3f-84044f8dde36" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_d2e401d1-fcbb-443d-b318-375cce9f662c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_4c4bd878-94a8-4676-9f3f-84044f8dde36" xlink:to="loc_us-gaap_StatementTable_d2e401d1-fcbb-443d-b318-375cce9f662c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_61082e26-c04a-4af4-b395-514c39b15e06" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_d2e401d1-fcbb-443d-b318-375cce9f662c" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_61082e26-c04a-4af4-b395-514c39b15e06" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_61082e26-c04a-4af4-b395-514c39b15e06_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_61082e26-c04a-4af4-b395-514c39b15e06" xlink:to="loc_us-gaap_EquityComponentDomain_61082e26-c04a-4af4-b395-514c39b15e06_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_b2a55cdb-4e06-4b33-816b-f35f879d9164" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_61082e26-c04a-4af4-b395-514c39b15e06" xlink:to="loc_us-gaap_EquityComponentDomain_b2a55cdb-4e06-4b33-816b-f35f879d9164" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_6b9aafa9-11c9-4b09-9af9-c78c9539063d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_b2a55cdb-4e06-4b33-816b-f35f879d9164" xlink:to="loc_us-gaap_CommonStockMember_6b9aafa9-11c9-4b09-9af9-c78c9539063d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_0cd579e9-a1c4-4a8e-883c-55468f6a55ea" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_b2a55cdb-4e06-4b33-816b-f35f879d9164" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_0cd579e9-a1c4-4a8e-883c-55468f6a55ea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_ae79772e-c1e2-4d27-babd-0dbf26fbd0cb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_b2a55cdb-4e06-4b33-816b-f35f879d9164" xlink:to="loc_us-gaap_RetainedEarningsMember_ae79772e-c1e2-4d27-babd-0dbf26fbd0cb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01f5e1b8-3b39-4837-ac62-e2d2b02638ca" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_b2a55cdb-4e06-4b33-816b-f35f879d9164" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01f5e1b8-3b39-4837-ac62-e2d2b02638ca" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_4c4bd878-94a8-4676-9f3f-84044f8dde36" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_05205600-d643-4bd1-94af-e4d39022f3a1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_05205600-d643-4bd1-94af-e4d39022f3a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_3b573b91-9ca1-4157-ab51-cd49b54a1d49" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockholdersEquity_3b573b91-9ca1-4157-ab51-cd49b54a1d49" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_1f58ec75-320f-452b-a356-f03eb2becc91" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_1f58ec75-320f-452b-a356-f03eb2becc91" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_b241a53b-29cc-4453-9173-4e64b7b72538" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_b241a53b-29cc-4453-9173-4e64b7b72538" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_75ed9a49-c335-4588-afed-ba714efeb243" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_75ed9a49-c335-4588-afed-ba714efeb243" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_82ca1724-8941-4dbf-91e3-cc1db48bdbe7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_82ca1724-8941-4dbf-91e3-cc1db48bdbe7" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_a8a85b9f-fd3e-42f5-a14e-c6a725b0464b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_a8a85b9f-fd3e-42f5-a14e-c6a725b0464b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_6adafe32-508d-4db0-b0c2-7ddd0c3c6a42" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_6adafe32-508d-4db0-b0c2-7ddd0c3c6a42" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_a1e83407-b4a6-4561-b3a4-4b20f6e06a43" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_a1e83407-b4a6-4561-b3a4-4b20f6e06a43" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_cd2ed569-9937-4ecb-a5f7-178f75df6cf9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_cd2ed569-9937-4ecb-a5f7-178f75df6cf9" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesAcquisitions_56ccbe64-b0c5-4f9f-8fad-5c815645343f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesAcquisitions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesAcquisitions_56ccbe64-b0c5-4f9f-8fad-5c815645343f" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueAcquisitions_020acab8-83a5-4f9e-9540-b45babe225c8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueAcquisitions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueAcquisitions_020acab8-83a5-4f9e-9540-b45babe225c8" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedOwnshareLendingArrangementIssuanceCosts_a64b972c-4c9a-4695-9bac-a96783058734" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedOwnshareLendingArrangementIssuanceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedOwnshareLendingArrangementIssuanceCosts_a64b972c-4c9a-4695-9bac-a96783058734" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_StockIssuedDuringPeriodSharesSettlementOfConvertibleNotes_4d11b45f-0e3a-4abf-88da-2f11e2d64e26" xlink:href="lifx-20250930.xsd#lifx_StockIssuedDuringPeriodSharesSettlementOfConvertibleNotes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_lifx_StockIssuedDuringPeriodSharesSettlementOfConvertibleNotes_4d11b45f-0e3a-4abf-88da-2f11e2d64e26" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_StockIssuedDuringPeriodValueSettlementOfConvertibleNotes_7b288998-876b-45be-bd7e-5a9a6e0ffc39" xlink:href="lifx-20250930.xsd#lifx_StockIssuedDuringPeriodValueSettlementOfConvertibleNotes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_lifx_StockIssuedDuringPeriodValueSettlementOfConvertibleNotes_7b288998-876b-45be-bd7e-5a9a6e0ffc39" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_10eb1ff9-1c8c-4e11-aaf3-cad8351b903c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_10eb1ff9-1c8c-4e11-aaf3-cad8351b903c" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_62402661-f3d9-4e06-9d79-4649d8956535" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_62402661-f3d9-4e06-9d79-4649d8956535" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_60df044c-5572-4d4d-af1d-1971e4badffc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_60df044c-5572-4d4d-af1d-1971e4badffc" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_0b0ff87d-d30f-4e26-b6c6-ed98c45732bd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_17b7d445-d681-4bca-9a1c-83da117c05ea" xlink:to="loc_us-gaap_NetIncomeLoss_0b0ff87d-d30f-4e26-b6c6-ed98c45732bd" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_9a8da111-f755-44bc-a30e-7ae2ebd59306" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_f4bf3e5d-2845-4d74-b7bd-31e8eb0630d6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/CondensedConsolidatedStatementsofCashFlows" xlink:type="simple" xlink:href="lifx-20250930.xsd#CondensedConsolidatedStatementsofCashFlows"/>
  <link:definitionLink xlink:role="http://lifx.com/role/CondensedConsolidatedStatementsofCashFlows" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_d82916f8-c11a-47f8-ba4f-6b3735d5f3ce" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_3a3315d4-95e0-46c6-9084-c10988ec7c47" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_d82916f8-c11a-47f8-ba4f-6b3735d5f3ce" xlink:to="loc_us-gaap_StatementTable_3a3315d4-95e0-46c6-9084-c10988ec7c47" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_d492e881-cfbd-4f0b-baba-c35e32f03b29" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_3a3315d4-95e0-46c6-9084-c10988ec7c47" xlink:to="loc_us-gaap_DebtInstrumentAxis_d492e881-cfbd-4f0b-baba-c35e32f03b29" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_d492e881-cfbd-4f0b-baba-c35e32f03b29_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_d492e881-cfbd-4f0b-baba-c35e32f03b29" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_d492e881-cfbd-4f0b-baba-c35e32f03b29_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_fb18984a-369a-4b95-8f86-ad0696a90b2b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_d492e881-cfbd-4f0b-baba-c35e32f03b29" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_fb18984a-369a-4b95-8f86-ad0696a90b2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_September2021ConvertibleNotesMember_84c11af6-63c4-45aa-ba6d-0bacbef0b7b2" xlink:href="lifx-20250930.xsd#lifx_September2021ConvertibleNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_fb18984a-369a-4b95-8f86-ad0696a90b2b" xlink:to="loc_lifx_September2021ConvertibleNotesMember_84c11af6-63c4-45aa-ba6d-0bacbef0b7b2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_July2021ConvertibleNotesMember_52d45a62-6a19-442e-9632-2677eaa7a30b" xlink:href="lifx-20250930.xsd#lifx_July2021ConvertibleNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_fb18984a-369a-4b95-8f86-ad0696a90b2b" xlink:to="loc_lifx_July2021ConvertibleNotesMember_52d45a62-6a19-442e-9632-2677eaa7a30b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_9877c659-5ccb-48a0-ae22-90521bc023bf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d82916f8-c11a-47f8-ba4f-6b3735d5f3ce" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_9877c659-5ccb-48a0-ae22-90521bc023bf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_bf956a5b-a565-4edd-b1f5-4cb4985e86b1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_9877c659-5ccb-48a0-ae22-90521bc023bf" xlink:to="loc_us-gaap_NetIncomeLoss_bf956a5b-a565-4edd-b1f5-4cb4985e86b1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_9877c659-5ccb-48a0-ae22-90521bc023bf" xlink:to="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_33e8d4f6-9446-41d7-865e-0e05d45da2bf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_33e8d4f6-9446-41d7-865e-0e05d45da2bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAmortization_9a1539e4-3c5f-4af6-b329-9a61332bcfa6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_CapitalizedContractCostAmortization_9a1539e4-3c5f-4af6-b329-9a61332bcfa6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_a891b29f-ee7c-47cb-bdfb-3517e4a7e365" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_a891b29f-ee7c-47cb-bdfb-3517e4a7e365" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_da5219ab-cbde-4b4e-aaab-f41295bf01e6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_ShareBasedCompensation_da5219ab-cbde-4b4e-aaab-f41295bf01e6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaidInKindInterest_80a07423-d424-4e2f-bc32-f51d562257ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaidInKindInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_PaidInKindInterest_80a07423-d424-4e2f-bc32-f51d562257ee" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_FairValueAdjustmentOfConvertibleNotes_b26f5b2b-1a6d-4a30-966a-4e8670faafda" xlink:href="lifx-20250930.xsd#lifx_FairValueAdjustmentOfConvertibleNotes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_lifx_FairValueAdjustmentOfConvertibleNotes_b26f5b2b-1a6d-4a30-966a-4e8670faafda" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_524bbfc4-f720-40a2-8fec-e3b09a59fbfe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_524bbfc4-f720-40a2-8fec-e3b09a59fbfe" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_e7d49ceb-459a-4920-b874-c23fd9b9aeed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_e7d49ceb-459a-4920-b874-c23fd9b9aeed" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfDerivatives_47c3337b-a5c1-4273-b787-c53149c32a3d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainLossOnSaleOfDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_GainLossOnSaleOfDerivatives_47c3337b-a5c1-4273-b787-c53149c32a3d" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_88c23689-4195-457d-bebf-42c4a834b854" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_88c23689-4195-457d-bebf-42c4a834b854" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNoncashIncomeExpense_14d7f66e-ce77-42b9-9d9c-f3b336affab6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNoncashIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_OtherNoncashIncomeExpense_14d7f66e-ce77-42b9-9d9c-f3b336affab6" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForDoubtfulAccounts_7bff014c-3b04-4afb-a7b1-d6d0f94a63fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProvisionForDoubtfulAccounts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_ProvisionForDoubtfulAccounts_7bff014c-3b04-4afb-a7b1-d6d0f94a63fa" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_c6227b65-df39-46a0-acb4-57a3dd615feb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_53003525-d97b-4461-b1c2-57a20a11a4c6" xlink:to="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_c6227b65-df39-46a0-acb4-57a3dd615feb" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_e5983f95-aa4b-4c8e-9877-821f615c1d57" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_c6227b65-df39-46a0-acb4-57a3dd615feb" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_e5983f95-aa4b-4c8e-9877-821f615c1d57" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_e9d89c77-ea35-40fc-a62a-30b95ecf10b1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_c6227b65-df39-46a0-acb4-57a3dd615feb" xlink:to="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_e9d89c77-ea35-40fc-a62a-30b95ecf10b1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_89abb674-f03e-4b20-ba29-4c39596aaa8e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInInventories"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_c6227b65-df39-46a0-acb4-57a3dd615feb" xlink:to="loc_us-gaap_IncreaseDecreaseInInventories_89abb674-f03e-4b20-ba29-4c39596aaa8e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerAsset_7a615d17-fe89-4145-9613-f3b8cbd24e59" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_c6227b65-df39-46a0-acb4-57a3dd615feb" xlink:to="loc_us-gaap_IncreaseDecreaseInContractWithCustomerAsset_7a615d17-fe89-4145-9613-f3b8cbd24e59" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayable_c14df97c-797c-4317-b00b-b98ddfe29375" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccountsPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_c6227b65-df39-46a0-acb4-57a3dd615feb" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayable_c14df97c-797c-4317-b00b-b98ddfe29375" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_79efada2-5470-4687-bd74-0e5a16eebba0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOtherAccruedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_c6227b65-df39-46a0-acb4-57a3dd615feb" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_79efada2-5470-4687-bd74-0e5a16eebba0" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_18811248-3f69-4a77-be50-7bd6b1fb82e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_c6227b65-df39-46a0-acb4-57a3dd615feb" xlink:to="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_18811248-3f69-4a77-be50-7bd6b1fb82e8" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_9e60ddc3-72c3-4111-addc-391f13c1c0f6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_c6227b65-df39-46a0-acb4-57a3dd615feb" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_9e60ddc3-72c3-4111-addc-391f13c1c0f6" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_63ef472b-bd18-470f-90eb-fc6a8efccc44" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_9877c659-5ccb-48a0-ae22-90521bc023bf" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_63ef472b-bd18-470f-90eb-fc6a8efccc44" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_a3b27c89-c8a3-4055-9caf-b1ccd08bdf3e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d82916f8-c11a-47f8-ba4f-6b3735d5f3ce" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_a3b27c89-c8a3-4055-9caf-b1ccd08bdf3e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_c57ebdd6-c564-49c2-a9ea-d5365152758f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_a3b27c89-c8a3-4055-9caf-b1ccd08bdf3e" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_c57ebdd6-c564-49c2-a9ea-d5365152758f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToDevelopSoftware_8252690b-e0e3-4324-a24a-7ba3f985bdf9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToDevelopSoftware"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_a3b27c89-c8a3-4055-9caf-b1ccd08bdf3e" xlink:to="loc_us-gaap_PaymentsToDevelopSoftware_8252690b-e0e3-4324-a24a-7ba3f985bdf9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_b86a41b9-585a-4578-bd84-e860ae525837" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_a3b27c89-c8a3-4055-9caf-b1ccd08bdf3e" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_b86a41b9-585a-4578-bd84-e860ae525837" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireLongtermInvestments_e5476f23-b891-4b57-9c19-0b470775618e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireLongtermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_a3b27c89-c8a3-4055-9caf-b1ccd08bdf3e" xlink:to="loc_us-gaap_PaymentsToAcquireLongtermInvestments_e5476f23-b891-4b57-9c19-0b470775618e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f28871a9-1b6c-4857-8f84-a8b6af2405fb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_a3b27c89-c8a3-4055-9caf-b1ccd08bdf3e" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f28871a9-1b6c-4857-8f84-a8b6af2405fb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_4d0f8ea9-2b0b-4ce4-9441-43ebc8bc1d89" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d82916f8-c11a-47f8-ba4f-6b3735d5f3ce" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_4d0f8ea9-2b0b-4ce4-9441-43ebc8bc1d89" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_ProceedsTaxWithholdingShareBasedPaymentArrangement_0ae45e86-37b7-437f-a058-b87c12b39f59" xlink:href="lifx-20250930.xsd#lifx_ProceedsTaxWithholdingShareBasedPaymentArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_4d0f8ea9-2b0b-4ce4-9441-43ebc8bc1d89" xlink:to="loc_lifx_ProceedsTaxWithholdingShareBasedPaymentArrangement_0ae45e86-37b7-437f-a058-b87c12b39f59" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_40ad870a-d44a-4f8c-8f8e-d5b50b90b6f0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_4d0f8ea9-2b0b-4ce4-9441-43ebc8bc1d89" xlink:to="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_40ad870a-d44a-4f8c-8f8e-d5b50b90b6f0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceInitialPublicOffering_9e9a0918-096f-469d-84ba-31ebc17c4545" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromIssuanceInitialPublicOffering"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_4d0f8ea9-2b0b-4ce4-9441-43ebc8bc1d89" xlink:to="loc_us-gaap_ProceedsFromIssuanceInitialPublicOffering_9e9a0918-096f-469d-84ba-31ebc17c4545" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfStockIssuanceCosts_2e741c78-573e-4d88-9f19-f14b5d655e6c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsOfStockIssuanceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_4d0f8ea9-2b0b-4ce4-9441-43ebc8bc1d89" xlink:to="loc_us-gaap_PaymentsOfStockIssuanceCosts_2e741c78-573e-4d88-9f19-f14b5d655e6c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromConvertibleDebt_5661dac6-f862-4466-8dbc-d626471db6ac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromConvertibleDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_4d0f8ea9-2b0b-4ce4-9441-43ebc8bc1d89" xlink:to="loc_us-gaap_ProceedsFromConvertibleDebt_5661dac6-f862-4466-8dbc-d626471db6ac" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDebtIssuanceCosts_9a75efd6-f34c-4bd6-9556-9045a5028f23" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsOfDebtIssuanceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_4d0f8ea9-2b0b-4ce4-9441-43ebc8bc1d89" xlink:to="loc_us-gaap_PaymentsOfDebtIssuanceCosts_9a75efd6-f34c-4bd6-9556-9045a5028f23" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForDerivativeInstrumentFinancingActivities_00b418f9-b533-426a-8983-3a41f3991e8d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsForDerivativeInstrumentFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_4d0f8ea9-2b0b-4ce4-9441-43ebc8bc1d89" xlink:to="loc_us-gaap_PaymentsForDerivativeInstrumentFinancingActivities_00b418f9-b533-426a-8983-3a41f3991e8d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_97166fe2-4de2-4405-b666-6f3bd41ac34b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_4d0f8ea9-2b0b-4ce4-9441-43ebc8bc1d89" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_97166fe2-4de2-4405-b666-6f3bd41ac34b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_b4951a4b-6fd7-4706-8235-3b116b3fbf02" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d82916f8-c11a-47f8-ba4f-6b3735d5f3ce" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_b4951a4b-6fd7-4706-8235-3b116b3fbf02" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_259eac02-edbe-458f-9469-5ee6ada8b82f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d82916f8-c11a-47f8-ba4f-6b3735d5f3ce" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_259eac02-edbe-458f-9469-5ee6ada8b82f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_48791d4c-fbd7-46dd-b6b2-cd00211a59d8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplementalCashFlowInformationAbstract_fc589fb3-4b4c-4111-a232-3e81b900f08b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SupplementalCashFlowInformationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d82916f8-c11a-47f8-ba4f-6b3735d5f3ce" xlink:to="loc_us-gaap_SupplementalCashFlowInformationAbstract_fc589fb3-4b4c-4111-a232-3e81b900f08b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxesPaidNet_9db3d048-8834-42bf-a9be-4f1f7a2dbd8c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxesPaidNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SupplementalCashFlowInformationAbstract_fc589fb3-4b4c-4111-a232-3e81b900f08b" xlink:to="loc_us-gaap_IncomeTaxesPaidNet_9db3d048-8834-42bf-a9be-4f1f7a2dbd8c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestPaidNet_9e73cd73-20f6-4e96-9b8d-129d7a437a4c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestPaidNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SupplementalCashFlowInformationAbstract_fc589fb3-4b4c-4111-a232-3e81b900f08b" xlink:to="loc_us-gaap_InterestPaidNet_9e73cd73-20f6-4e96-9b8d-129d7a437a4c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeasePayments_9248aab3-143d-4d78-90dd-f3c433ee4ba3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeasePayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SupplementalCashFlowInformationAbstract_fc589fb3-4b4c-4111-a232-3e81b900f08b" xlink:to="loc_us-gaap_OperatingLeasePayments_9248aab3-143d-4d78-90dd-f3c433ee4ba3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_ff1599a9-fac1-43a6-af8b-222a08f4c1a3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d82916f8-c11a-47f8-ba4f-6b3735d5f3ce" xlink:to="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_ff1599a9-fac1-43a6-af8b-222a08f4c1a3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_1726dc4d-1c5b-4a8d-ab53-bdab67f0f312" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_ff1599a9-fac1-43a6-af8b-222a08f4c1a3" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_1726dc4d-1c5b-4a8d-ab53-bdab67f0f312" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConversionOfStockAmountIssued1_53d74ece-5ce0-4f8f-959c-f5f5791e2e0e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConversionOfStockAmountIssued1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_ff1599a9-fac1-43a6-af8b-222a08f4c1a3" xlink:to="loc_us-gaap_ConversionOfStockAmountIssued1_53d74ece-5ce0-4f8f-959c-f5f5791e2e0e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalExpendituresIncurredButNotYetPaid_0933b2c5-86fc-4918-be0c-4c54b40a4f4a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalExpendituresIncurredButNotYetPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_ff1599a9-fac1-43a6-af8b-222a08f4c1a3" xlink:to="loc_us-gaap_CapitalExpendituresIncurredButNotYetPaid_0933b2c5-86fc-4918-be0c-4c54b40a4f4a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_StockBasedCompensationExpenseIncurredButNotYetPaid_7e1fa6cd-a146-4e87-99b9-c3b1c4e17504" xlink:href="lifx-20250930.xsd#lifx_StockBasedCompensationExpenseIncurredButNotYetPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_ff1599a9-fac1-43a6-af8b-222a08f4c1a3" xlink:to="loc_lifx_StockBasedCompensationExpenseIncurredButNotYetPaid_7e1fa6cd-a146-4e87-99b9-c3b1c4e17504" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_StockIssuanceCostsIncurredButNotYetPaid_29701adc-4610-4331-bd5f-ceab5431130a" xlink:href="lifx-20250930.xsd#lifx_StockIssuanceCostsIncurredButNotYetPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_ff1599a9-fac1-43a6-af8b-222a08f4c1a3" xlink:to="loc_lifx_StockIssuanceCostsIncurredButNotYetPaid_29701adc-4610-4331-bd5f-ceab5431130a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransferToInvestments_4d1c5ba2-9806-494a-bb5a-b920c607fd46" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransferToInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_ff1599a9-fac1-43a6-af8b-222a08f4c1a3" xlink:to="loc_us-gaap_TransferToInvestments_4d1c5ba2-9806-494a-bb5a-b920c607fd46" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAbstract_3573e9f9-464d-4567-99d0-b1d7b5f1f03e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d82916f8-c11a-47f8-ba4f-6b3735d5f3ce" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAbstract_3573e9f9-464d-4567-99d0-b1d7b5f1f03e" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_a1c9d778-3596-4300-beb8-11a0eb6f848d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAbstract_3573e9f9-464d-4567-99d0-b1d7b5f1f03e" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_a1c9d778-3596-4300-beb8-11a0eb6f848d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashNoncurrent_5c06ee4f-624d-47ed-976c-22507712c8aa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAbstract_3573e9f9-464d-4567-99d0-b1d7b5f1f03e" xlink:to="loc_us-gaap_RestrictedCashNoncurrent_5c06ee4f-624d-47ed-976c-22507712c8aa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_51d828b0-1620-4bc4-991b-b6c2b685ef72" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/CondensedConsolidatedStatementsofCashFlowsParenthetical" xlink:type="simple" xlink:href="lifx-20250930.xsd#CondensedConsolidatedStatementsofCashFlowsParenthetical"/>
  <link:definitionLink xlink:role="http://lifx.com/role/CondensedConsolidatedStatementsofCashFlowsParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_5bf7c23f-9881-4437-905d-8bf5f4960d0a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_21259d59-81fb-4881-a5a4-c92118cf9c87" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_5bf7c23f-9881-4437-905d-8bf5f4960d0a" xlink:to="loc_us-gaap_StatementTable_21259d59-81fb-4881-a5a4-c92118cf9c87" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_76656e4b-7e58-4750-8272-9d7a246aa11a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_21259d59-81fb-4881-a5a4-c92118cf9c87" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_76656e4b-7e58-4750-8272-9d7a246aa11a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_76656e4b-7e58-4750-8272-9d7a246aa11a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_76656e4b-7e58-4750-8272-9d7a246aa11a" xlink:to="loc_us-gaap_RelatedPartyDomain_76656e4b-7e58-4750-8272-9d7a246aa11a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_243404f9-6834-4b37-9ac0-e7381accfd9b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_76656e4b-7e58-4750-8272-9d7a246aa11a" xlink:to="loc_us-gaap_RelatedPartyDomain_243404f9-6834-4b37-9ac0-e7381accfd9b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_5a075fc2-9b2f-4571-b7d4-27deace9c401" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_243404f9-6834-4b37-9ac0-e7381accfd9b" xlink:to="loc_us-gaap_RelatedPartyMember_5a075fc2-9b2f-4571-b7d4-27deace9c401" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_8eb1636a-4609-4d85-a193-8a09577698a3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_5bf7c23f-9881-4437-905d-8bf5f4960d0a" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_8eb1636a-4609-4d85-a193-8a09577698a3" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/NatureofBusinessDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#NatureofBusinessDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/NatureofBusinessDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockLineItems_562a5bba-c690-45d6-a983-0be7f32640e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsidiarySaleOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSubsidiaryOrEquityMethodInvesteeTable_8eae4036-2295-46ad-8804-36ed564319d6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfSubsidiaryOrEquityMethodInvesteeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_562a5bba-c690-45d6-a983-0be7f32640e7" xlink:to="loc_us-gaap_ScheduleOfSubsidiaryOrEquityMethodInvesteeTable_8eae4036-2295-46ad-8804-36ed564319d6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_559116e6-8976-4ab0-9e1b-b8f6a8a6b732" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsidiarySaleOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSubsidiaryOrEquityMethodInvesteeTable_8eae4036-2295-46ad-8804-36ed564319d6" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_559116e6-8976-4ab0-9e1b-b8f6a8a6b732" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_559116e6-8976-4ab0-9e1b-b8f6a8a6b732_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_559116e6-8976-4ab0-9e1b-b8f6a8a6b732" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_559116e6-8976-4ab0-9e1b-b8f6a8a6b732_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_5edcf583-179c-482f-b714-d94f0f851360" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_559116e6-8976-4ab0-9e1b-b8f6a8a6b732" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_5edcf583-179c-482f-b714-d94f0f851360" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IPOMember_b3014d97-773a-4e51-bea3-3a9c9d324e4d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IPOMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_5edcf583-179c-482f-b714-d94f0f851360" xlink:to="loc_us-gaap_IPOMember_b3014d97-773a-4e51-bea3-3a9c9d324e4d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OverAllotmentOptionMember_16c7a014-5355-4651-b877-d6e7e2b0ecc6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OverAllotmentOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_5edcf583-179c-482f-b714-d94f0f851360" xlink:to="loc_us-gaap_OverAllotmentOptionMember_16c7a014-5355-4651-b877-d6e7e2b0ecc6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_ec65d85f-b246-4d87-926b-692cf192741f" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSubsidiaryOrEquityMethodInvesteeTable_8eae4036-2295-46ad-8804-36ed564319d6" xlink:to="loc_dei_LegalEntityAxis_ec65d85f-b246-4d87-926b-692cf192741f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_ec65d85f-b246-4d87-926b-692cf192741f_default" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_ec65d85f-b246-4d87-926b-692cf192741f" xlink:to="loc_dei_EntityDomain_ec65d85f-b246-4d87-926b-692cf192741f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_2f2f9f0a-ee17-488c-973b-28e59b96a70b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_ec65d85f-b246-4d87-926b-692cf192741f" xlink:to="loc_dei_EntityDomain_2f2f9f0a-ee17-488c-973b-28e59b96a70b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_SellingSecurityholdersMember_6241e27b-572f-4ce4-a639-b92e23c5cadb" xlink:href="lifx-20250930.xsd#lifx_SellingSecurityholdersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_2f2f9f0a-ee17-488c-973b-28e59b96a70b" xlink:to="loc_lifx_SellingSecurityholdersMember_6241e27b-572f-4ce4-a639-b92e23c5cadb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_4fb7393d-8420-40a5-9b65-ef135876a458" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_562a5bba-c690-45d6-a983-0be7f32640e7" xlink:to="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_4fb7393d-8420-40a5-9b65-ef135876a458" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockPricePerShare_4c9eae44-ac3b-47ac-bd29-3baeeac9af76" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_562a5bba-c690-45d6-a983-0be7f32640e7" xlink:to="loc_us-gaap_SaleOfStockPricePerShare_4c9eae44-ac3b-47ac-bd29-3baeeac9af76" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_de116a51-b218-4844-9842-a2c452c80db2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_562a5bba-c690-45d6-a983-0be7f32640e7" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_de116a51-b218-4844-9842-a2c452c80db2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfStockIssuanceCosts_d1cd75d3-021c-4e1c-a1e9-25513a81fdbf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsOfStockIssuanceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_562a5bba-c690-45d6-a983-0be7f32640e7" xlink:to="loc_us-gaap_PaymentsOfStockIssuanceCosts_d1cd75d3-021c-4e1c-a1e9-25513a81fdbf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_PaymentOfExpensesOnBehalfOfSellingStockholders_07fcbbc5-3075-49e6-aa91-5b52a27518ed" xlink:href="lifx-20250930.xsd#lifx_PaymentOfExpensesOnBehalfOfSellingStockholders"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_562a5bba-c690-45d6-a983-0be7f32640e7" xlink:to="loc_lifx_PaymentOfExpensesOnBehalfOfSellingStockholders_07fcbbc5-3075-49e6-aa91-5b52a27518ed" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_b18a7af8-0cb6-4931-81b1-63b0847d9a09" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_562a5bba-c690-45d6-a983-0be7f32640e7" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_b18a7af8-0cb6-4931-81b1-63b0847d9a09" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/SummaryofSignificantAccountingPoliciesScheduleofChannelandRetailPartnersWhoRepresentedGreaterThan10ofRevenueorAccountsReceivableDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#SummaryofSignificantAccountingPoliciesScheduleofChannelandRetailPartnersWhoRepresentedGreaterThan10ofRevenueorAccountsReceivableDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/SummaryofSignificantAccountingPoliciesScheduleofChannelandRetailPartnersWhoRepresentedGreaterThan10ofRevenueorAccountsReceivableDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskLineItems_032a8347-6348-4d7e-8e80-d709896fdf51" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTable_9fc22657-117c-4e5d-be98-9aa494dcc1cd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_032a8347-6348-4d7e-8e80-d709896fdf51" xlink:to="loc_us-gaap_ConcentrationRiskTable_9fc22657-117c-4e5d-be98-9aa494dcc1cd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_c04dffb7-25ad-4c91-8bcd-989b84c1c479" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9fc22657-117c-4e5d-be98-9aa494dcc1cd" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_c04dffb7-25ad-4c91-8bcd-989b84c1c479" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_c04dffb7-25ad-4c91-8bcd-989b84c1c479_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_c04dffb7-25ad-4c91-8bcd-989b84c1c479" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_c04dffb7-25ad-4c91-8bcd-989b84c1c479_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_ffbbe6a4-9a4a-4760-b70e-c621fa12a379" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_c04dffb7-25ad-4c91-8bcd-989b84c1c479" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_ffbbe6a4-9a4a-4760-b70e-c621fa12a379" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember_543c1e7a-e0c1-46aa-b661-bd7889d74423" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_ffbbe6a4-9a4a-4760-b70e-c621fa12a379" xlink:to="loc_us-gaap_CustomerConcentrationRiskMember_543c1e7a-e0c1-46aa-b661-bd7889d74423" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_56894579-ecbb-4e73-9ca5-8b5916e95c52" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9fc22657-117c-4e5d-be98-9aa494dcc1cd" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_56894579-ecbb-4e73-9ca5-8b5916e95c52" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_56894579-ecbb-4e73-9ca5-8b5916e95c52_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_56894579-ecbb-4e73-9ca5-8b5916e95c52" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_56894579-ecbb-4e73-9ca5-8b5916e95c52_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_b59532d6-416b-4237-b008-719224755d49" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_56894579-ecbb-4e73-9ca5-8b5916e95c52" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_b59532d6-416b-4237-b008-719224755d49" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SalesRevenueNetMember_de9080b6-74d2-45f2-942e-37e9229f335f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SalesRevenueNetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_b59532d6-416b-4237-b008-719224755d49" xlink:to="loc_us-gaap_SalesRevenueNetMember_de9080b6-74d2-45f2-942e-37e9229f335f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableMember_697c35fc-560d-42a0-8b5a-a3c6dd79ff5c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_b59532d6-416b-4237-b008-719224755d49" xlink:to="loc_us-gaap_AccountsReceivableMember_697c35fc-560d-42a0-8b5a-a3c6dd79ff5c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_eec735b6-333d-4d2d-8ac8-a46de83c9a72" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9fc22657-117c-4e5d-be98-9aa494dcc1cd" xlink:to="loc_srt_MajorCustomersAxis_eec735b6-333d-4d2d-8ac8-a46de83c9a72" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_eec735b6-333d-4d2d-8ac8-a46de83c9a72_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_eec735b6-333d-4d2d-8ac8-a46de83c9a72" xlink:to="loc_srt_NameOfMajorCustomerDomain_eec735b6-333d-4d2d-8ac8-a46de83c9a72_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_b34da9c6-1da2-43ef-a96f-51f6a8ad478d" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_eec735b6-333d-4d2d-8ac8-a46de83c9a72" xlink:to="loc_srt_NameOfMajorCustomerDomain_b34da9c6-1da2-43ef-a96f-51f6a8ad478d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_ChannelPartnerAppleMember_d92fa3fe-d488-4443-9e90-18d84a65a4a1" xlink:href="lifx-20250930.xsd#lifx_ChannelPartnerAppleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_b34da9c6-1da2-43ef-a96f-51f6a8ad478d" xlink:to="loc_lifx_ChannelPartnerAppleMember_d92fa3fe-d488-4443-9e90-18d84a65a4a1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_ChannelPartnerGoogleMember_e54dfd17-2b3e-4770-bca8-c9c106957cad" xlink:href="lifx-20250930.xsd#lifx_ChannelPartnerGoogleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_b34da9c6-1da2-43ef-a96f-51f6a8ad478d" xlink:to="loc_lifx_ChannelPartnerGoogleMember_e54dfd17-2b3e-4770-bca8-c9c106957cad" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_DataPartnerAMember_9ddc3e9b-b1bd-4293-ade0-3e261dde0435" xlink:href="lifx-20250930.xsd#lifx_DataPartnerAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_b34da9c6-1da2-43ef-a96f-51f6a8ad478d" xlink:to="loc_lifx_DataPartnerAMember_9ddc3e9b-b1bd-4293-ade0-3e261dde0435" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RetailPartnerAMember_7a7d4c56-54ae-4b73-898f-fe3c0f38ead2" xlink:href="lifx-20250930.xsd#lifx_RetailPartnerAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_b34da9c6-1da2-43ef-a96f-51f6a8ad478d" xlink:to="loc_lifx_RetailPartnerAMember_7a7d4c56-54ae-4b73-898f-fe3c0f38ead2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_ee90bbc0-1a08-43b2-bd40-521fa47d59ae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_032a8347-6348-4d7e-8e80-d709896fdf51" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_ee90bbc0-1a08-43b2-bd40-521fa47d59ae" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/SegmentandGeographicRevenueDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#SegmentandGeographicRevenueDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/SegmentandGeographicRevenueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_28ea4714-166e-4ef1-9b73-85ad95450f71" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_ee91b365-67fc-412e-8d80-6884be18af60" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_28ea4714-166e-4ef1-9b73-85ad95450f71" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_ee91b365-67fc-412e-8d80-6884be18af60" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_41954bb6-78d9-46c5-82e1-8ae49e08ac63" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_ee91b365-67fc-412e-8d80-6884be18af60" xlink:to="loc_srt_StatementGeographicalAxis_41954bb6-78d9-46c5-82e1-8ae49e08ac63" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_41954bb6-78d9-46c5-82e1-8ae49e08ac63_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_41954bb6-78d9-46c5-82e1-8ae49e08ac63" xlink:to="loc_srt_SegmentGeographicalDomain_41954bb6-78d9-46c5-82e1-8ae49e08ac63_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_04f6a345-a550-494a-ae8a-a190d23c6786" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_41954bb6-78d9-46c5-82e1-8ae49e08ac63" xlink:to="loc_srt_SegmentGeographicalDomain_04f6a345-a550-494a-ae8a-a190d23c6786" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NorthAmericaMember_ba36eae6-839c-484e-9ae2-6e96f30c2462" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NorthAmericaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_04f6a345-a550-494a-ae8a-a190d23c6786" xlink:to="loc_srt_NorthAmericaMember_ba36eae6-839c-484e-9ae2-6e96f30c2462" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_422e5549-b9bd-4a8d-881b-998e946c11f0" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NorthAmericaMember_ba36eae6-839c-484e-9ae2-6e96f30c2462" xlink:to="loc_country_US_422e5549-b9bd-4a8d-881b-998e946c11f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EMEAMember_7be11ae9-1f07-4319-bab0-8f0a14072012" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EMEAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_04f6a345-a550-494a-ae8a-a190d23c6786" xlink:to="loc_us-gaap_EMEAMember_7be11ae9-1f07-4319-bab0-8f0a14072012" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_OtherInternationalRegionsMember_fc806f1d-2456-43e7-882f-45eb8a47a635" xlink:href="lifx-20250930.xsd#lifx_OtherInternationalRegionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_04f6a345-a550-494a-ae8a-a190d23c6786" xlink:to="loc_lifx_OtherInternationalRegionsMember_fc806f1d-2456-43e7-882f-45eb8a47a635" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_0b8bdf3e-879d-4543-b4d9-0072005ddc20" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_ee91b365-67fc-412e-8d80-6884be18af60" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_0b8bdf3e-879d-4543-b4d9-0072005ddc20" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_0b8bdf3e-879d-4543-b4d9-0072005ddc20_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_0b8bdf3e-879d-4543-b4d9-0072005ddc20" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_0b8bdf3e-879d-4543-b4d9-0072005ddc20_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_8bc35536-88ae-4c2e-ae8b-ad6a5a897622" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_0b8bdf3e-879d-4543-b4d9-0072005ddc20" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_8bc35536-88ae-4c2e-ae8b-ad6a5a897622" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerMember_26b2a478-d1b0-47fa-936c-9cf70e72a9fc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_8bc35536-88ae-4c2e-ae8b-ad6a5a897622" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerMember_26b2a478-d1b0-47fa-936c-9cf70e72a9fc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_9db7304c-66ba-4099-b79d-21165272c68a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_ee91b365-67fc-412e-8d80-6884be18af60" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_9db7304c-66ba-4099-b79d-21165272c68a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_9db7304c-66ba-4099-b79d-21165272c68a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_9db7304c-66ba-4099-b79d-21165272c68a" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_9db7304c-66ba-4099-b79d-21165272c68a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_c1d5ef44-3625-48a7-8626-f9546b80aec6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_9db7304c-66ba-4099-b79d-21165272c68a" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_c1d5ef44-3625-48a7-8626-f9546b80aec6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicConcentrationRiskMember_25c9df8c-e950-493a-9747-c1fd3d26f988" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeographicConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_c1d5ef44-3625-48a7-8626-f9546b80aec6" xlink:to="loc_us-gaap_GeographicConcentrationRiskMember_25c9df8c-e950-493a-9747-c1fd3d26f988" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_ec414f36-f3c9-4d40-8887-769cd06bf249" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_28ea4714-166e-4ef1-9b73-85ad95450f71" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_ec414f36-f3c9-4d40-8887-769cd06bf249" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_aa6f86d3-911a-42fb-a720-81d17e7a430e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_28ea4714-166e-4ef1-9b73-85ad95450f71" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_aa6f86d3-911a-42fb-a720-81d17e7a430e" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/DeferredRevenueDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#DeferredRevenueDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/DeferredRevenueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_ee66f556-e90a-4deb-a9dc-3e45e328f176" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_a6dc8e58-150f-4f05-adc4-59093d8bb5a6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_ee66f556-e90a-4deb-a9dc-3e45e328f176" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_a6dc8e58-150f-4f05-adc4-59093d8bb5a6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_16845865-058e-466f-aeb5-4f23ab897d81" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_a6dc8e58-150f-4f05-adc4-59093d8bb5a6" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_16845865-058e-466f-aeb5-4f23ab897d81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation_e78bb0f2-9386-4f56-a976-8f2b85f326e3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_ee66f556-e90a-4deb-a9dc-3e45e328f176" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligation_e78bb0f2-9386-4f56-a976-8f2b85f326e3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_26f3270c-139c-4dbf-9707-10aa120f769f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_ee66f556-e90a-4deb-a9dc-3e45e328f176" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_26f3270c-139c-4dbf-9707-10aa120f769f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_3d104589-d4f2-44c1-b05b-af35b4ab86da" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_ee66f556-e90a-4deb-a9dc-3e45e328f176" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_3d104589-d4f2-44c1-b05b-af35b4ab86da" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/DeferredRevenueDetails_1" xlink:type="simple" xlink:href="lifx-20250930.xsd#DeferredRevenueDetails_1"/>
  <link:definitionLink xlink:role="http://lifx.com/role/DeferredRevenueDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_ee66f556-e90a-4deb-a9dc-3e45e328f176" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_a6dc8e58-150f-4f05-adc4-59093d8bb5a6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_ee66f556-e90a-4deb-a9dc-3e45e328f176" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_a6dc8e58-150f-4f05-adc4-59093d8bb5a6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation_e78bb0f2-9386-4f56-a976-8f2b85f326e3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_ee66f556-e90a-4deb-a9dc-3e45e328f176" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligation_e78bb0f2-9386-4f56-a976-8f2b85f326e3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_26f3270c-139c-4dbf-9707-10aa120f769f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_ee66f556-e90a-4deb-a9dc-3e45e328f176" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_26f3270c-139c-4dbf-9707-10aa120f769f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_3d104589-d4f2-44c1-b05b-af35b4ab86da" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_ee66f556-e90a-4deb-a9dc-3e45e328f176" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_3d104589-d4f2-44c1-b05b-af35b4ab86da" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/FairValueMeasurementsScheduleofFairValueandClassificationofInstrumentsDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#FairValueMeasurementsScheduleofFairValueandClassificationofInstrumentsDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/FairValueMeasurementsScheduleofFairValueandClassificationofInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_84036afd-0813-46eb-8a80-6cdc5e11edc2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8d732a51-613c-4dce-8dc4-cedff2a0de77" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_84036afd-0813-46eb-8a80-6cdc5e11edc2" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8d732a51-613c-4dce-8dc4-cedff2a0de77" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_b0401832-43f8-4ce6-bd9f-9a2cb4584158" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8d732a51-613c-4dce-8dc4-cedff2a0de77" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_b0401832-43f8-4ce6-bd9f-9a2cb4584158" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_b0401832-43f8-4ce6-bd9f-9a2cb4584158_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_b0401832-43f8-4ce6-bd9f-9a2cb4584158" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_b0401832-43f8-4ce6-bd9f-9a2cb4584158_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_34f0cc88-6485-4f08-bc2d-268f55bbcec2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_b0401832-43f8-4ce6-bd9f-9a2cb4584158" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_34f0cc88-6485-4f08-bc2d-268f55bbcec2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_c72bfbc3-e1d0-4d93-9be9-2a349e09fb80" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_34f0cc88-6485-4f08-bc2d-268f55bbcec2" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_c72bfbc3-e1d0-4d93-9be9-2a349e09fb80" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_90c1c01e-16a7-4c31-83af-439d157c4adb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_34f0cc88-6485-4f08-bc2d-268f55bbcec2" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_90c1c01e-16a7-4c31-83af-439d157c4adb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_54dcb86a-b818-4095-9493-b8c3f5cf0f24" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_34f0cc88-6485-4f08-bc2d-268f55bbcec2" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_54dcb86a-b818-4095-9493-b8c3f5cf0f24" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_e0f567aa-dca1-4878-ac08-b5699eb279fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_84036afd-0813-46eb-8a80-6cdc5e11edc2" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_e0f567aa-dca1-4878-ac08-b5699eb279fa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashEquivalentsAtCarryingValue_e86aa52c-d81d-48b5-a3d6-f9fde0288ec2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_e0f567aa-dca1-4878-ac08-b5699eb279fa" xlink:to="loc_us-gaap_CashEquivalentsAtCarryingValue_e86aa52c-d81d-48b5-a3d6-f9fde0288ec2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableFairValueDisclosure_49c9b0b2-0e93-4ab6-812a-f37cd2d75829" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NotesReceivableFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_e0f567aa-dca1-4878-ac08-b5699eb279fa" xlink:to="loc_us-gaap_NotesReceivableFairValueDisclosure_49c9b0b2-0e93-4ab6-812a-f37cd2d75829" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_28376b69-f143-4895-8d87-fb9db6abf6b7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_e0f567aa-dca1-4878-ac08-b5699eb279fa" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_28376b69-f143-4895-8d87-fb9db6abf6b7" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/FairValueMeasurementsScheduleofChangeinFairValueofLevel3InstrumentsDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#FairValueMeasurementsScheduleofChangeinFairValueofLevel3InstrumentsDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/FairValueMeasurementsScheduleofChangeinFairValueofLevel3InstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_640a06e6-ca33-47d4-935c-3993668131cc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_263c880e-f922-47ad-a911-cc155b1166af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_640a06e6-ca33-47d4-935c-3993668131cc" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_263c880e-f922-47ad-a911-cc155b1166af" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_c9facf1c-9a3e-4306-95cd-e757c7f03751" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByAssetClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_263c880e-f922-47ad-a911-cc155b1166af" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_c9facf1c-9a3e-4306-95cd-e757c7f03751" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_c9facf1c-9a3e-4306-95cd-e757c7f03751_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_c9facf1c-9a3e-4306-95cd-e757c7f03751" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_c9facf1c-9a3e-4306-95cd-e757c7f03751_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_2c0b655a-4cfb-450b-8d26-ae2caeb515e1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_c9facf1c-9a3e-4306-95cd-e757c7f03751" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_2c0b655a-4cfb-450b-8d26-ae2caeb515e1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableMember_20e07b37-32ea-43a2-8b82-86e759f759d2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NotesReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_2c0b655a-4cfb-450b-8d26-ae2caeb515e1" xlink:to="loc_us-gaap_NotesReceivableMember_20e07b37-32ea-43a2-8b82-86e759f759d2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_f452b4f9-e8e7-4fa7-9b4d-9906ced4ff1e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_640a06e6-ca33-47d4-935c-3993668131cc" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_f452b4f9-e8e7-4fa7-9b4d-9906ced4ff1e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_ddc8714d-dd36-4d83-bf1c-e2f27cba0268" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_f452b4f9-e8e7-4fa7-9b4d-9906ced4ff1e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_ddc8714d-dd36-4d83-bf1c-e2f27cba0268" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_7357318a-2ae0-4e3f-a17c-3c3779c02690" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_f452b4f9-e8e7-4fa7-9b4d-9906ced4ff1e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_7357318a-2ae0-4e3f-a17c-3c3779c02690" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_a4e6238f-a6c8-4d93-8bba-3c78c9611cf9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_f452b4f9-e8e7-4fa7-9b4d-9906ced4ff1e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_a4e6238f-a6c8-4d93-8bba-3c78c9611cf9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_df539f45-5446-4c35-8758-fff889d0ca6f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/FairValueMeasurementsNarrativeDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#FairValueMeasurementsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/FairValueMeasurementsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_fe8dfdd3-cdae-4b92-acd9-046d56733f23" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_9ef91bba-200d-43ac-994b-35186e6e849f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_fe8dfdd3-cdae-4b92-acd9-046d56733f23" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_9ef91bba-200d-43ac-994b-35186e6e849f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_6d76a97e-1d23-4d31-81c5-04fdeb5fb273" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_9ef91bba-200d-43ac-994b-35186e6e849f" xlink:to="loc_srt_CounterpartyNameAxis_6d76a97e-1d23-4d31-81c5-04fdeb5fb273" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_6d76a97e-1d23-4d31-81c5-04fdeb5fb273_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_6d76a97e-1d23-4d31-81c5-04fdeb5fb273" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_6d76a97e-1d23-4d31-81c5-04fdeb5fb273_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_c1605eca-5e3f-4a8f-93ee-39e74d3f591e" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_6d76a97e-1d23-4d31-81c5-04fdeb5fb273" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_c1605eca-5e3f-4a8f-93ee-39e74d3f591e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_AuraConsolidatedGroupIncMember_04d6cea3-96e8-4131-8a0f-5d257f8f221c" xlink:href="lifx-20250930.xsd#lifx_AuraConsolidatedGroupIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_c1605eca-5e3f-4a8f-93ee-39e74d3f591e" xlink:to="loc_lifx_AuraConsolidatedGroupIncMember_04d6cea3-96e8-4131-8a0f-5d257f8f221c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_HubbleNetworkIncMember_0dc29511-b764-489b-a526-7a9ce6dfc84d" xlink:href="lifx-20250930.xsd#lifx_HubbleNetworkIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_c1605eca-5e3f-4a8f-93ee-39e74d3f591e" xlink:to="loc_lifx_HubbleNetworkIncMember_0dc29511-b764-489b-a526-7a9ce6dfc84d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_65cfc973-518d-4d4f-a284-a107706e6d25" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_9ef91bba-200d-43ac-994b-35186e6e849f" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_65cfc973-518d-4d4f-a284-a107706e6d25" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_65cfc973-518d-4d4f-a284-a107706e6d25_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_65cfc973-518d-4d4f-a284-a107706e6d25" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_65cfc973-518d-4d4f-a284-a107706e6d25_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_4d849c0a-3c3e-43a7-aa13-bbaeb3d9b9fa" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_65cfc973-518d-4d4f-a284-a107706e6d25" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_4d849c0a-3c3e-43a7-aa13-bbaeb3d9b9fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_ConvertibleNoteInvestmentMember_008ddffb-0e78-47b9-a9aa-6f337e38c218" xlink:href="lifx-20250930.xsd#lifx_ConvertibleNoteInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_4d849c0a-3c3e-43a7-aa13-bbaeb3d9b9fa" xlink:to="loc_lifx_ConvertibleNoteInvestmentMember_008ddffb-0e78-47b9-a9aa-6f337e38c218" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember_fca3171a-7102-4f80-a37a-94066136d5d0" xlink:href="lifx-20250930.xsd#lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_4d849c0a-3c3e-43a7-aa13-bbaeb3d9b9fa" xlink:to="loc_lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember_fca3171a-7102-4f80-a37a-94066136d5d0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_AdvertisingPartnershipAndRevenueSharingAgreementTerm_866a44d5-1f6f-4d72-8b5f-25ed290f23ac" xlink:href="lifx-20250930.xsd#lifx_AdvertisingPartnershipAndRevenueSharingAgreementTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_fe8dfdd3-cdae-4b92-acd9-046d56733f23" xlink:to="loc_lifx_AdvertisingPartnershipAndRevenueSharingAgreementTerm_866a44d5-1f6f-4d72-8b5f-25ed290f23ac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireLongtermInvestments_736fa4b6-8b06-49a6-be42-6d2b9c69d9a3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireLongtermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_fe8dfdd3-cdae-4b92-acd9-046d56733f23" xlink:to="loc_us-gaap_PaymentsToAcquireLongtermInvestments_736fa4b6-8b06-49a6-be42-6d2b9c69d9a3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_423bafc9-1d44-4c36-be69-8ca23220dc3f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_fe8dfdd3-cdae-4b92-acd9-046d56733f23" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_423bafc9-1d44-4c36-be69-8ca23220dc3f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermInvestments_021f0106-ec97-4222-a2a8-7fad204b2c09" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_fe8dfdd3-cdae-4b92-acd9-046d56733f23" xlink:to="loc_us-gaap_LongTermInvestments_021f0106-ec97-4222-a2a8-7fad204b2c09" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/BusinessCombinationsDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#BusinessCombinationsDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/BusinessCombinationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_f67cb500-e413-4dd7-b660-51c0cb81f3b5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_296b9af3-aa3b-4de5-b0c0-7b8d90864f4b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f67cb500-e413-4dd7-b660-51c0cb81f3b5" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_296b9af3-aa3b-4de5-b0c0-7b8d90864f4b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_d445ed1b-f2d2-462a-afb1-b37ecc48b6ab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_296b9af3-aa3b-4de5-b0c0-7b8d90864f4b" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_d445ed1b-f2d2-462a-afb1-b37ecc48b6ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_d445ed1b-f2d2-462a-afb1-b37ecc48b6ab_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_d445ed1b-f2d2-462a-afb1-b37ecc48b6ab" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_d445ed1b-f2d2-462a-afb1-b37ecc48b6ab_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f49d7caf-91a3-4c7b-bdc9-5e7ea7c625da" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_d445ed1b-f2d2-462a-afb1-b37ecc48b6ab" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f49d7caf-91a3-4c7b-bdc9-5e7ea7c625da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_FantixIncMember_5d378a7e-b6b9-49e1-8aae-8840f0d0a5ca" xlink:href="lifx-20250930.xsd#lifx_FantixIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f49d7caf-91a3-4c7b-bdc9-5e7ea7c625da" xlink:to="loc_lifx_FantixIncMember_5d378a7e-b6b9-49e1-8aae-8840f0d0a5ca" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_5e1636a9-e497-47fb-9070-be6f61868f77" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f67cb500-e413-4dd7-b660-51c0cb81f3b5" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_5e1636a9-e497-47fb-9070-be6f61868f77" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_PaymentsToAcquireBusinessesGrossAndAmountPayableWithinOneYear_93540e7c-83e1-450b-9d69-34547c39ea2b" xlink:href="lifx-20250930.xsd#lifx_PaymentsToAcquireBusinessesGrossAndAmountPayableWithinOneYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f67cb500-e413-4dd7-b660-51c0cb81f3b5" xlink:to="loc_lifx_PaymentsToAcquireBusinessesGrossAndAmountPayableWithinOneYear_93540e7c-83e1-450b-9d69-34547c39ea2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_d607baaf-e9fa-4a8d-8a04-1d56f23638b5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f67cb500-e413-4dd7-b660-51c0cb81f3b5" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_d607baaf-e9fa-4a8d-8a04-1d56f23638b5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_9e1447c1-9bfb-417d-9ec2-677ba42c5810" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireBusinessesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f67cb500-e413-4dd7-b660-51c0cb81f3b5" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_9e1447c1-9bfb-417d-9ec2-677ba42c5810" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_BusinessCombinationConsiderationTransferredAmountPayableWithinOneYear_b3be64b8-7a95-4502-a666-591982e4df91" xlink:href="lifx-20250930.xsd#lifx_BusinessCombinationConsiderationTransferredAmountPayableWithinOneYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f67cb500-e413-4dd7-b660-51c0cb81f3b5" xlink:to="loc_lifx_BusinessCombinationConsiderationTransferredAmountPayableWithinOneYear_b3be64b8-7a95-4502-a666-591982e4df91" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_508fe5e4-adcd-487b-93fe-037168e954c5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f67cb500-e413-4dd7-b660-51c0cb81f3b5" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_508fe5e4-adcd-487b-93fe-037168e954c5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_b082fb27-24c4-4832-9f63-b542604ba0eb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f67cb500-e413-4dd7-b660-51c0cb81f3b5" xlink:to="loc_us-gaap_Goodwill_b082fb27-24c4-4832-9f63-b542604ba0eb" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/BalanceSheetComponentsScheduleofPropertyandEquipmentNetDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#BalanceSheetComponentsScheduleofPropertyandEquipmentNetDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/BalanceSheetComponentsScheduleofPropertyandEquipmentNetDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_cbb83250-2df5-44d4-86a5-8a231630abd9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_1cbd8153-fb5e-41da-a4a9-27c322db0f50" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_cbb83250-2df5-44d4-86a5-8a231630abd9" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_1cbd8153-fb5e-41da-a4a9-27c322db0f50" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_ba62fcb8-bb51-454a-86b4-a7f6b1d0aaa6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_1cbd8153-fb5e-41da-a4a9-27c322db0f50" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_ba62fcb8-bb51-454a-86b4-a7f6b1d0aaa6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_ba62fcb8-bb51-454a-86b4-a7f6b1d0aaa6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_ba62fcb8-bb51-454a-86b4-a7f6b1d0aaa6" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_ba62fcb8-bb51-454a-86b4-a7f6b1d0aaa6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd2186a0-6b47-4d67-91b1-cc76b9cafbb0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_ba62fcb8-bb51-454a-86b4-a7f6b1d0aaa6" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd2186a0-6b47-4d67-91b1-cc76b9cafbb0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComputerEquipmentMember_2c569a74-d2db-4644-8040-62571bdbc89c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComputerEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd2186a0-6b47-4d67-91b1-cc76b9cafbb0" xlink:to="loc_us-gaap_ComputerEquipmentMember_2c569a74-d2db-4644-8040-62571bdbc89c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseholdImprovementsMember_7114cce1-35ca-403f-956c-c9092edac313" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseholdImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd2186a0-6b47-4d67-91b1-cc76b9cafbb0" xlink:to="loc_us-gaap_LeaseholdImprovementsMember_7114cce1-35ca-403f-956c-c9092edac313" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_ProductionManufacturingEquipmentMember_d3ae162c-08bb-4892-a81d-d202a811ef87" xlink:href="lifx-20250930.xsd#lifx_ProductionManufacturingEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd2186a0-6b47-4d67-91b1-cc76b9cafbb0" xlink:to="loc_lifx_ProductionManufacturingEquipmentMember_d3ae162c-08bb-4892-a81d-d202a811ef87" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConstructionInProgressMember_e572b9b0-44c7-4840-bdac-e7a33e028e0d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConstructionInProgressMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd2186a0-6b47-4d67-91b1-cc76b9cafbb0" xlink:to="loc_us-gaap_ConstructionInProgressMember_e572b9b0-44c7-4840-bdac-e7a33e028e0d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FurnitureAndFixturesMember_f159b838-55a5-4898-a34f-822e688aeff4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FurnitureAndFixturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_dd2186a0-6b47-4d67-91b1-cc76b9cafbb0" xlink:to="loc_us-gaap_FurnitureAndFixturesMember_f159b838-55a5-4898-a34f-822e688aeff4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_de242028-f136-4924-9226-937580d7de45" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_cbb83250-2df5-44d4-86a5-8a231630abd9" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_de242028-f136-4924-9226-937580d7de45" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_e7d5a200-eec9-4416-bd14-f1816319e87d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_cbb83250-2df5-44d4-86a5-8a231630abd9" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_e7d5a200-eec9-4416-bd14-f1816319e87d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_4a2d6f6c-1d13-43be-89dd-9da0e2fcf3ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_cbb83250-2df5-44d4-86a5-8a231630abd9" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_4a2d6f6c-1d13-43be-89dd-9da0e2fcf3ba" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/BalanceSheetComponentsNarrativeDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#BalanceSheetComponentsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/BalanceSheetComponentsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_68cdcb6d-1960-4a50-9e3c-923e14ac8dda" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_68cdcb6d-1960-4a50-9e3c-923e14ac8dda" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_b7880af5-cdfe-445a-a301-c7e9e872a01a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_68cdcb6d-1960-4a50-9e3c-923e14ac8dda" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_b7880af5-cdfe-445a-a301-c7e9e872a01a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_b7880af5-cdfe-445a-a301-c7e9e872a01a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_b7880af5-cdfe-445a-a301-c7e9e872a01a" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_b7880af5-cdfe-445a-a301-c7e9e872a01a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_28741edd-8b12-427b-8d3c-356ebf5641e6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_b7880af5-cdfe-445a-a301-c7e9e872a01a" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_28741edd-8b12-427b-8d3c-356ebf5641e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_FantixIncMember_3c62261a-d50d-41f5-a913-e4b2bfbbac97" xlink:href="lifx-20250930.xsd#lifx_FantixIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_28741edd-8b12-427b-8d3c-356ebf5641e6" xlink:to="loc_lifx_FantixIncMember_3c62261a-d50d-41f5-a913-e4b2bfbbac97" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Depreciation_9acb6ef9-227a-45dc-9127-8b95b1e34e99" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Depreciation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:to="loc_us-gaap_Depreciation_9acb6ef9-227a-45dc-9127-8b95b1e34e99" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairmentOfLongLivedAssetsHeldForUse_1693becf-333c-47c0-9b02-e76666643b21" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairmentOfLongLivedAssetsHeldForUse"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:to="loc_us-gaap_ImpairmentOfLongLivedAssetsHeldForUse_1693becf-333c-47c0-9b02-e76666643b21" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseRemainingLeaseTerm_c620c615-a538-401c-aa5b-e690bbacbb8d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseRemainingLeaseTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:to="loc_us-gaap_LesseeOperatingLeaseRemainingLeaseTerm_c620c615-a538-401c-aa5b-e690bbacbb8d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_148f2a27-dfa6-4b29-950a-9cf5773ce08d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:to="loc_us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_148f2a27-dfa6-4b29-950a-9cf5773ce08d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedComputerSoftwareAdditions_8988ee37-bbe4-4f5d-8de4-46297cdcf5a0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedComputerSoftwareAdditions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:to="loc_us-gaap_CapitalizedComputerSoftwareAdditions_8988ee37-bbe4-4f5d-8de4-46297cdcf5a0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_771ad084-51c5-491e-a887-ad0fc8b7014f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_771ad084-51c5-491e-a887-ad0fc8b7014f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairmentOfIntangibleAssetsExcludingGoodwill_500c7f03-1106-4c89-b768-e39448dc375c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairmentOfIntangibleAssetsExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:to="loc_us-gaap_ImpairmentOfIntangibleAssetsExcludingGoodwill_500c7f03-1106-4c89-b768-e39448dc375c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_2a71f266-a5ed-402c-b683-bf9680a0c65e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:to="loc_us-gaap_Goodwill_2a71f266-a5ed-402c-b683-bf9680a0c65e" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_39322adb-4110-4bb6-853c-1c8a97d9dc5e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0db45a35-faf0-402e-bfd1-6db40a0788d5" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_39322adb-4110-4bb6-853c-1c8a97d9dc5e" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/BalanceSheetComponentsScheduleofPrepaidExpensesandOtherAssetsNonCurrentDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#BalanceSheetComponentsScheduleofPrepaidExpensesandOtherAssetsNonCurrentDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/BalanceSheetComponentsScheduleofPrepaidExpensesandOtherAssetsNonCurrentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_e7de7112-5b66-4772-9f59-079c54282286" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_7552a3d5-80da-4939-baab-362f4c8e781d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_e7de7112-5b66-4772-9f59-079c54282286" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_7552a3d5-80da-4939-baab-362f4c8e781d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_c3cb4e72-2b06-456c-ae85-665cce46ec45" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_7552a3d5-80da-4939-baab-362f4c8e781d" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_c3cb4e72-2b06-456c-ae85-665cce46ec45" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_c3cb4e72-2b06-456c-ae85-665cce46ec45_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_c3cb4e72-2b06-456c-ae85-665cce46ec45" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_c3cb4e72-2b06-456c-ae85-665cce46ec45_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_d207933c-7c87-4483-b3c2-1098084ecce8" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_c3cb4e72-2b06-456c-ae85-665cce46ec45" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_d207933c-7c87-4483-b3c2-1098084ecce8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_ConvertibleNoteInvestmentMember_148b922d-74af-44c1-8cee-c55033674fac" xlink:href="lifx-20250930.xsd#lifx_ConvertibleNoteInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_d207933c-7c87-4483-b3c2-1098084ecce8" xlink:to="loc_lifx_ConvertibleNoteInvestmentMember_148b922d-74af-44c1-8cee-c55033674fac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_DataRevenuePartnerWarrantMember_95fb4c42-0322-451a-98c5-67b5d3762f0c" xlink:href="lifx-20250930.xsd#lifx_DataRevenuePartnerWarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_d207933c-7c87-4483-b3c2-1098084ecce8" xlink:to="loc_lifx_DataRevenuePartnerWarrantMember_95fb4c42-0322-451a-98c5-67b5d3762f0c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RelatedPartyInvestmentMember_6525b0c4-7f16-43f8-ab58-9cae500fa027" xlink:href="lifx-20250930.xsd#lifx_RelatedPartyInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_d207933c-7c87-4483-b3c2-1098084ecce8" xlink:to="loc_lifx_RelatedPartyInvestmentMember_6525b0c4-7f16-43f8-ab58-9cae500fa027" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RelatedPartyWarrantMember_9453d8f2-a70f-43ff-bd5f-75c60a584c74" xlink:href="lifx-20250930.xsd#lifx_RelatedPartyWarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_d207933c-7c87-4483-b3c2-1098084ecce8" xlink:to="loc_lifx_RelatedPartyWarrantMember_9453d8f2-a70f-43ff-bd5f-75c60a584c74" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember_1c5b6424-75ae-4a72-87b8-f9dc0cbd9877" xlink:href="lifx-20250930.xsd#lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_d207933c-7c87-4483-b3c2-1098084ecce8" xlink:to="loc_lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember_1c5b6424-75ae-4a72-87b8-f9dc0cbd9877" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepaidExpenseNoncurrent_44b165bd-ba5f-44d9-8feb-1507f933598b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_e7de7112-5b66-4772-9f59-079c54282286" xlink:to="loc_us-gaap_PrepaidExpenseNoncurrent_44b165bd-ba5f-44d9-8feb-1507f933598b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermInvestments_61f7bf82-e4ae-40ef-9f69-827dcfb86b79" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_e7de7112-5b66-4772-9f59-079c54282286" xlink:to="loc_us-gaap_LongTermInvestments_61f7bf82-e4ae-40ef-9f69-827dcfb86b79" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsNoncurrent_892c9d5d-25d0-429a-beb3-7740b49fac7f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseAndOtherAssetsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_e7de7112-5b66-4772-9f59-079c54282286" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsNoncurrent_892c9d5d-25d0-429a-beb3-7740b49fac7f" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/BalanceSheetComponentsScheduleofGoodwillandIntangibleAssetsNetDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#BalanceSheetComponentsScheduleofGoodwillandIntangibleAssetsNetDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/BalanceSheetComponentsScheduleofGoodwillandIntangibleAssetsNetDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_1063ba55-82a9-44af-9123-a8e0efc5e4ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_8983345d-1881-4aae-91fc-8106d71ea098" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_1063ba55-82a9-44af-9123-a8e0efc5e4ee" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_8983345d-1881-4aae-91fc-8106d71ea098" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_bf81b90d-59c5-43cf-91a0-57d183b32c20" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_8983345d-1881-4aae-91fc-8106d71ea098" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_bf81b90d-59c5-43cf-91a0-57d183b32c20" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_bf81b90d-59c5-43cf-91a0-57d183b32c20_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_bf81b90d-59c5-43cf-91a0-57d183b32c20" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_bf81b90d-59c5-43cf-91a0-57d183b32c20_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_accc9642-26ba-47dd-8314-7c28f93a2b1c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_bf81b90d-59c5-43cf-91a0-57d183b32c20" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_accc9642-26ba-47dd-8314-7c28f93a2b1c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradeNamesMember_9e290287-2a1e-41b3-9732-6a7403388e69" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TradeNamesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_accc9642-26ba-47dd-8314-7c28f93a2b1c" xlink:to="loc_us-gaap_TradeNamesMember_9e290287-2a1e-41b3-9732-6a7403388e69" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TechnologyBasedIntangibleAssetsMember_9bd34de8-6666-43ef-b86a-9d318362ac1b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TechnologyBasedIntangibleAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_accc9642-26ba-47dd-8314-7c28f93a2b1c" xlink:to="loc_us-gaap_TechnologyBasedIntangibleAssetsMember_9bd34de8-6666-43ef-b86a-9d318362ac1b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_10dfb763-9a21-4f39-9b79-794f495a02fe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_accc9642-26ba-47dd-8314-7c28f93a2b1c" xlink:to="loc_us-gaap_CustomerRelationshipsMember_10dfb763-9a21-4f39-9b79-794f495a02fe" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_97826c80-7ee4-4604-84fc-e86c3c67e28f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SoftwareAndSoftwareDevelopmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_accc9642-26ba-47dd-8314-7c28f93a2b1c" xlink:to="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_97826c80-7ee4-4604-84fc-e86c3c67e28f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_10f06a10-5e07-40ab-aa38-05dcc0e0303e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_1063ba55-82a9-44af-9123-a8e0efc5e4ee" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_10f06a10-5e07-40ab-aa38-05dcc0e0303e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_c7f08f26-6c38-4d87-a6ce-fed32c03cf4a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_1063ba55-82a9-44af-9123-a8e0efc5e4ee" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_c7f08f26-6c38-4d87-a6ce-fed32c03cf4a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_123800cc-a881-4e70-9706-cf464e68649e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_1063ba55-82a9-44af-9123-a8e0efc5e4ee" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_123800cc-a881-4e70-9706-cf464e68649e" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/BalanceSheetComponentsScheduleofIntangibleAssetsWeightedAverageRemainingUsefulLifeDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#BalanceSheetComponentsScheduleofIntangibleAssetsWeightedAverageRemainingUsefulLifeDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/BalanceSheetComponentsScheduleofIntangibleAssetsWeightedAverageRemainingUsefulLifeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_750d4007-ea33-46b2-b801-2be168d459e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_5d39d58a-8707-441b-84af-b60f4978efa3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_750d4007-ea33-46b2-b801-2be168d459e7" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_5d39d58a-8707-441b-84af-b60f4978efa3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_9f1fe0d1-1276-473a-aa78-5dbf45c48cd1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_5d39d58a-8707-441b-84af-b60f4978efa3" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_9f1fe0d1-1276-473a-aa78-5dbf45c48cd1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_9f1fe0d1-1276-473a-aa78-5dbf45c48cd1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_9f1fe0d1-1276-473a-aa78-5dbf45c48cd1" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_9f1fe0d1-1276-473a-aa78-5dbf45c48cd1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_693ecb82-8a94-48fc-b6bb-e8844d4ade41" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_9f1fe0d1-1276-473a-aa78-5dbf45c48cd1" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_693ecb82-8a94-48fc-b6bb-e8844d4ade41" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradeNamesMember_a835a67f-7b11-4ad0-a80d-b1ecb5a22d6a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TradeNamesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_693ecb82-8a94-48fc-b6bb-e8844d4ade41" xlink:to="loc_us-gaap_TradeNamesMember_a835a67f-7b11-4ad0-a80d-b1ecb5a22d6a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TechnologyBasedIntangibleAssetsMember_8142a8f9-f756-4a5d-befa-89ef6a488250" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TechnologyBasedIntangibleAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_693ecb82-8a94-48fc-b6bb-e8844d4ade41" xlink:to="loc_us-gaap_TechnologyBasedIntangibleAssetsMember_8142a8f9-f756-4a5d-befa-89ef6a488250" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_68c8668d-f260-4485-af57-9c73e41f1ced" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_693ecb82-8a94-48fc-b6bb-e8844d4ade41" xlink:to="loc_us-gaap_CustomerRelationshipsMember_68c8668d-f260-4485-af57-9c73e41f1ced" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_c1bc2b22-64ee-494f-b99c-2831c41dda1e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SoftwareAndSoftwareDevelopmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_693ecb82-8a94-48fc-b6bb-e8844d4ade41" xlink:to="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_c1bc2b22-64ee-494f-b99c-2831c41dda1e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_03a7ed17-2dcd-4041-9c0b-f38b647d9bb7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_750d4007-ea33-46b2-b801-2be168d459e7" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_03a7ed17-2dcd-4041-9c0b-f38b647d9bb7" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/ConvertibleNotesNarrativeDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#ConvertibleNotesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/ConvertibleNotesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_b4cb09ba-5760-4ef0-a573-32a979e45793" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentTable_b4cb09ba-5760-4ef0-a573-32a979e45793" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_47feb98d-5c04-49b7-9518-ce9d160499b2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_b4cb09ba-5760-4ef0-a573-32a979e45793" xlink:to="loc_us-gaap_DebtInstrumentAxis_47feb98d-5c04-49b7-9518-ce9d160499b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_47feb98d-5c04-49b7-9518-ce9d160499b2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_47feb98d-5c04-49b7-9518-ce9d160499b2" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_47feb98d-5c04-49b7-9518-ce9d160499b2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_ad8dca8b-1ef9-43c1-b08c-87d971baa002" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_47feb98d-5c04-49b7-9518-ce9d160499b2" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_ad8dca8b-1ef9-43c1-b08c-87d971baa002" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_June2025ConvertibleNotesMember_d25722f6-6252-4694-b9f2-0c6c7866fcae" xlink:href="lifx-20250930.xsd#lifx_June2025ConvertibleNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_ad8dca8b-1ef9-43c1-b08c-87d971baa002" xlink:to="loc_lifx_June2025ConvertibleNotesMember_d25722f6-6252-4694-b9f2-0c6c7866fcae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_3b5a64ea-cdcf-4a95-ba86-88419b3d643d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_b4cb09ba-5760-4ef0-a573-32a979e45793" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_3b5a64ea-cdcf-4a95-ba86-88419b3d643d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_3b5a64ea-cdcf-4a95-ba86-88419b3d643d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_3b5a64ea-cdcf-4a95-ba86-88419b3d643d" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_3b5a64ea-cdcf-4a95-ba86-88419b3d643d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_40bb718b-183c-4140-955a-0a76c107ce77" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_3b5a64ea-cdcf-4a95-ba86-88419b3d643d" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_40bb718b-183c-4140-955a-0a76c107ce77" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtMember_ab250c2f-fb19-42c6-9bd1-535388947381" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_40bb718b-183c-4140-955a-0a76c107ce77" xlink:to="loc_us-gaap_ConvertibleDebtMember_ab250c2f-fb19-42c6-9bd1-535388947381" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_DebtInstrumentConvertibleTermsOfConversionAxis_9096bb2e-a737-4301-8584-fc28009c7749" xlink:href="lifx-20250930.xsd#lifx_DebtInstrumentConvertibleTermsOfConversionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_b4cb09ba-5760-4ef0-a573-32a979e45793" xlink:to="loc_lifx_DebtInstrumentConvertibleTermsOfConversionAxis_9096bb2e-a737-4301-8584-fc28009c7749" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_DebtInstrumentConvertibleTermsOfConversionDomain_9096bb2e-a737-4301-8584-fc28009c7749_default" xlink:href="lifx-20250930.xsd#lifx_DebtInstrumentConvertibleTermsOfConversionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_lifx_DebtInstrumentConvertibleTermsOfConversionAxis_9096bb2e-a737-4301-8584-fc28009c7749" xlink:to="loc_lifx_DebtInstrumentConvertibleTermsOfConversionDomain_9096bb2e-a737-4301-8584-fc28009c7749_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_DebtInstrumentConvertibleTermsOfConversionDomain_36f7fa17-02a7-4196-9017-f5c174c950f4" xlink:href="lifx-20250930.xsd#lifx_DebtInstrumentConvertibleTermsOfConversionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_lifx_DebtInstrumentConvertibleTermsOfConversionAxis_9096bb2e-a737-4301-8584-fc28009c7749" xlink:to="loc_lifx_DebtInstrumentConvertibleTermsOfConversionDomain_36f7fa17-02a7-4196-9017-f5c174c950f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_DebtConversionTermsOneMember_9e9036ce-cbff-4a5c-9af6-17aad40a528c" xlink:href="lifx-20250930.xsd#lifx_DebtConversionTermsOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_lifx_DebtInstrumentConvertibleTermsOfConversionDomain_36f7fa17-02a7-4196-9017-f5c174c950f4" xlink:to="loc_lifx_DebtConversionTermsOneMember_9e9036ce-cbff-4a5c-9af6-17aad40a528c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_DebtConversionTermsTwoMember_0d50ee54-5973-4445-9f08-16114d522271" xlink:href="lifx-20250930.xsd#lifx_DebtConversionTermsTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_lifx_DebtInstrumentConvertibleTermsOfConversionDomain_36f7fa17-02a7-4196-9017-f5c174c950f4" xlink:to="loc_lifx_DebtConversionTermsTwoMember_0d50ee54-5973-4445-9f08-16114d522271" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_2541156c-3eac-41f7-a688-6671a074d708" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_2541156c-3eac-41f7-a688-6671a074d708" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_2c4b2984-3004-4c19-9003-8f06d658672e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_2c4b2984-3004-4c19-9003-8f06d658672e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentConvertibleConversionRatio1_3919d2d9-a3aa-44a0-ab7b-23e14960b620" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentConvertibleConversionRatio1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentConvertibleConversionRatio1_3919d2d9-a3aa-44a0-ab7b-23e14960b620" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_3fde923d-bba9-4fb4-9e29-a97879137b74" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentConvertibleConversionPrice1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_3fde923d-bba9-4fb4-9e29-a97879137b74" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_DebtInstrumentConvertibleMakeWholeFundamentalChangeMinimumConversionPrice_8713e396-776d-48b3-a420-886c7319a878" xlink:href="lifx-20250930.xsd#lifx_DebtInstrumentConvertibleMakeWholeFundamentalChangeMinimumConversionPrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_lifx_DebtInstrumentConvertibleMakeWholeFundamentalChangeMinimumConversionPrice_8713e396-776d-48b3-a420-886c7319a878" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_DebtInstrumentConvertibleMakeWholeFundamentalChangeConversionRatioMaximum_36414d80-5548-40e0-ac75-ae7a28523678" xlink:href="lifx-20250930.xsd#lifx_DebtInstrumentConvertibleMakeWholeFundamentalChangeConversionRatioMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_lifx_DebtInstrumentConvertibleMakeWholeFundamentalChangeConversionRatioMaximum_36414d80-5548-40e0-ac75-ae7a28523678" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentConvertibleThresholdTradingDays_cfcfe50d-751a-4881-b1bf-9534ebafb2f0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentConvertibleThresholdTradingDays"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentConvertibleThresholdTradingDays_cfcfe50d-751a-4881-b1bf-9534ebafb2f0" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_be70b541-49a6-43fe-8db2-8234b585e81a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_be70b541-49a6-43fe-8db2-8234b585e81a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_40ba8960-35c9-42f0-8cd6-681d19789051" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_40ba8960-35c9-42f0-8cd6-681d19789051" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPricePercentage_863eaf02-97e1-47d9-b81e-acc1703c384d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentRedemptionPricePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPricePercentage_863eaf02-97e1-47d9-b81e-acc1703c384d" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateDuringPeriod_0b736243-f06c-4af8-b32c-6c8af50940b3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentInterestRateDuringPeriod_0b736243-f06c-4af8-b32c-6c8af50940b3" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_e14ecb48-df0f-43da-8e3e-2b18d2de27e0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_InterestExpenseDebt_e14ecb48-df0f-43da-8e3e-2b18d2de27e0" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFairValue_d6ca106f-43ce-4b3d-99ea-40b4ece3a0d5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_DebtInstrumentFairValue_d6ca106f-43ce-4b3d-99ea-40b4ece3a0d5" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OptionIndexedToIssuersEquityStrikePrice1_ccdd3528-8f6a-4f49-bed8-3fc90aed7c18" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OptionIndexedToIssuersEquityStrikePrice1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_OptionIndexedToIssuersEquityStrikePrice1_ccdd3528-8f6a-4f49-bed8-3fc90aed7c18" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_OptionIndexedToIssuersEquityCapPrice_79e22a10-655a-46d3-a893-830566601e38" xlink:href="lifx-20250930.xsd#lifx_OptionIndexedToIssuersEquityCapPrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_lifx_OptionIndexedToIssuersEquityCapPrice_79e22a10-655a-46d3-a893-830566601e38" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedOwnshareLendingArrangementIssuanceCosts_d7c85ef5-869a-420b-972f-9c5f09236a2d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedOwnshareLendingArrangementIssuanceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_c4663d96-f3a4-4e69-9cab-2ead79ce566e" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedOwnshareLendingArrangementIssuanceCosts_d7c85ef5-869a-420b-972f-9c5f09236a2d" xlink:type="arc" order="15"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/ConvertibleNotesScheduleofNetCarryingAmountofConvertibleNotesDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#ConvertibleNotesScheduleofNetCarryingAmountofConvertibleNotesDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/ConvertibleNotesScheduleofNetCarryingAmountofConvertibleNotesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_d5166234-d99e-4d3e-b131-dbee8f635530" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_7e34beb2-2639-4843-a4d7-014c12912ba8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_d5166234-d99e-4d3e-b131-dbee8f635530" xlink:to="loc_us-gaap_DebtInstrumentTable_7e34beb2-2639-4843-a4d7-014c12912ba8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_a0175fa8-a0ec-4c32-9566-81bf2d1e0971" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_7e34beb2-2639-4843-a4d7-014c12912ba8" xlink:to="loc_us-gaap_DebtInstrumentAxis_a0175fa8-a0ec-4c32-9566-81bf2d1e0971" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_a0175fa8-a0ec-4c32-9566-81bf2d1e0971_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_a0175fa8-a0ec-4c32-9566-81bf2d1e0971" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_a0175fa8-a0ec-4c32-9566-81bf2d1e0971_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_c7149bf8-c3fb-409b-b2da-b5b4df2ce7c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_a0175fa8-a0ec-4c32-9566-81bf2d1e0971" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_c7149bf8-c3fb-409b-b2da-b5b4df2ce7c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_June2025ConvertibleNotesMember_5af8ff8d-d54e-47bf-a472-9ec66c071b02" xlink:href="lifx-20250930.xsd#lifx_June2025ConvertibleNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_c7149bf8-c3fb-409b-b2da-b5b4df2ce7c9" xlink:to="loc_lifx_June2025ConvertibleNotesMember_5af8ff8d-d54e-47bf-a472-9ec66c071b02" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_15e9e22a-116c-4a1a-833e-4a32aa6116e0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_7e34beb2-2639-4843-a4d7-014c12912ba8" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_15e9e22a-116c-4a1a-833e-4a32aa6116e0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_15e9e22a-116c-4a1a-833e-4a32aa6116e0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_15e9e22a-116c-4a1a-833e-4a32aa6116e0" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_15e9e22a-116c-4a1a-833e-4a32aa6116e0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_65c54345-c626-4de9-a4e7-abcb335513b8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_15e9e22a-116c-4a1a-833e-4a32aa6116e0" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_65c54345-c626-4de9-a4e7-abcb335513b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtMember_04d49dca-b15f-4197-8965-b8f7a327680b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_65c54345-c626-4de9-a4e7-abcb335513b8" xlink:to="loc_us-gaap_ConvertibleDebtMember_04d49dca-b15f-4197-8965-b8f7a327680b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_17785102-3a01-4dc6-a3c7-a4b7eb3bd49e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_d5166234-d99e-4d3e-b131-dbee8f635530" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_17785102-3a01-4dc6-a3c7-a4b7eb3bd49e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_bfc78958-22c6-4c51-91a2-2828b6d5a2f3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredFinanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_d5166234-d99e-4d3e-b131-dbee8f635530" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_bfc78958-22c6-4c51-91a2-2828b6d5a2f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtNoncurrent_8ffec4a7-37c1-4c5f-be60-18aedab23b13" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_d5166234-d99e-4d3e-b131-dbee8f635530" xlink:to="loc_us-gaap_ConvertibleDebtNoncurrent_8ffec4a7-37c1-4c5f-be60-18aedab23b13" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/CommitmentsandContingenciesLitigationandArbitrationDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#CommitmentsandContingenciesLitigationandArbitrationDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/CommitmentsandContingenciesLitigationandArbitrationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_036bc175-9e6a-49ff-8bdc-83c24b6855b2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_8c554ac0-a828-4933-9a23-f4d223a14d5b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_036bc175-9e6a-49ff-8bdc-83c24b6855b2" xlink:to="loc_us-gaap_LossContingenciesTable_8c554ac0-a828-4933-9a23-f4d223a14d5b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseAxis_6420b159-71a7-4694-a7f5-9fbc2576d62a" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_LitigationCaseAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_8c554ac0-a828-4933-9a23-f4d223a14d5b" xlink:to="loc_srt_LitigationCaseAxis_6420b159-71a7-4694-a7f5-9fbc2576d62a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseTypeDomain_6420b159-71a7-4694-a7f5-9fbc2576d62a_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_LitigationCaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_LitigationCaseAxis_6420b159-71a7-4694-a7f5-9fbc2576d62a" xlink:to="loc_srt_LitigationCaseTypeDomain_6420b159-71a7-4694-a7f5-9fbc2576d62a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseTypeDomain_f24f63ae-5bf5-4335-bec5-772de51da5d3" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_LitigationCaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_LitigationCaseAxis_6420b159-71a7-4694-a7f5-9fbc2576d62a" xlink:to="loc_srt_LitigationCaseTypeDomain_f24f63ae-5bf5-4335-bec5-772de51da5d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_PatentInfringementClaimMember_4f55949b-7473-43c1-a228-bf94b174ff05" xlink:href="lifx-20250930.xsd#lifx_PatentInfringementClaimMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_f24f63ae-5bf5-4335-bec5-772de51da5d3" xlink:to="loc_lifx_PatentInfringementClaimMember_4f55949b-7473-43c1-a228-bf94b174ff05" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyClaimsDismissedNumber_64ebae49-b45c-41d9-8d9d-e9d17eae6593" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingencyClaimsDismissedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_036bc175-9e6a-49ff-8bdc-83c24b6855b2" xlink:to="loc_us-gaap_LossContingencyClaimsDismissedNumber_64ebae49-b45c-41d9-8d9d-e9d17eae6593" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyPendingClaimsNumber_4eba1583-e1fe-4165-997e-16239873c830" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingencyPendingClaimsNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_036bc175-9e6a-49ff-8bdc-83c24b6855b2" xlink:to="loc_us-gaap_LossContingencyPendingClaimsNumber_4eba1583-e1fe-4165-997e-16239873c830" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/CommonStockDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#CommonStockDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/CommonStockDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_33999937-661e-4a16-87f5-48e7387299d2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_93fcb8d9-07d4-4d19-bce9-2d6173dfc86d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_33999937-661e-4a16-87f5-48e7387299d2" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_93fcb8d9-07d4-4d19-bce9-2d6173dfc86d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_07fdf6ac-d139-4fc5-9b7c-022efb6eaf0e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_93fcb8d9-07d4-4d19-bce9-2d6173dfc86d" xlink:to="loc_us-gaap_StatementClassOfStockAxis_07fdf6ac-d139-4fc5-9b7c-022efb6eaf0e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_07fdf6ac-d139-4fc5-9b7c-022efb6eaf0e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_07fdf6ac-d139-4fc5-9b7c-022efb6eaf0e" xlink:to="loc_us-gaap_ClassOfStockDomain_07fdf6ac-d139-4fc5-9b7c-022efb6eaf0e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_e02429d6-5a3f-4bcb-a32f-063f1343d2f4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_07fdf6ac-d139-4fc5-9b7c-022efb6eaf0e" xlink:to="loc_us-gaap_ClassOfStockDomain_e02429d6-5a3f-4bcb-a32f-063f1343d2f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockCompensationPlanMember_c9247553-7c4e-46d3-88bb-6637c0f41fc9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockCompensationPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_e02429d6-5a3f-4bcb-a32f-063f1343d2f4" xlink:to="loc_us-gaap_StockCompensationPlanMember_c9247553-7c4e-46d3-88bb-6637c0f41fc9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_811d2c18-6b85-4112-b61b-b965b6b9fdb9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_e02429d6-5a3f-4bcb-a32f-063f1343d2f4" xlink:to="loc_us-gaap_WarrantMember_811d2c18-6b85-4112-b61b-b965b6b9fdb9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_f8ee90e7-0414-4a06-b39a-c6a4b049f6f2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_e02429d6-5a3f-4bcb-a32f-063f1343d2f4" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_f8ee90e7-0414-4a06-b39a-c6a4b049f6f2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_SharesToBeGrantedMember_f8a331dc-c35f-41bb-8a8a-93446e6e20a3" xlink:href="lifx-20250930.xsd#lifx_SharesToBeGrantedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_e02429d6-5a3f-4bcb-a32f-063f1343d2f4" xlink:to="loc_lifx_SharesToBeGrantedMember_f8a331dc-c35f-41bb-8a8a-93446e6e20a3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_7662c1b7-1caf-4ca7-ae38-4fa98428f82f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_33999937-661e-4a16-87f5-48e7387299d2" xlink:to="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_7662c1b7-1caf-4ca7-ae38-4fa98428f82f" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/EquityIncentivePlanNarrativeDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#EquityIncentivePlanNarrativeDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/EquityIncentivePlanNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_71d09928-eed6-4d35-955a-f24ce343e946" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_02f616e9-4b86-4c0a-8e96-47b70e5ec8e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_71d09928-eed6-4d35-955a-f24ce343e946" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_02f616e9-4b86-4c0a-8e96-47b70e5ec8e7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_68a447cb-bb09-4510-83f0-16601dd965a9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_02f616e9-4b86-4c0a-8e96-47b70e5ec8e7" xlink:to="loc_us-gaap_AwardTypeAxis_68a447cb-bb09-4510-83f0-16601dd965a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_68a447cb-bb09-4510-83f0-16601dd965a9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_68a447cb-bb09-4510-83f0-16601dd965a9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_68a447cb-bb09-4510-83f0-16601dd965a9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_5a5e5881-1354-4018-aa16-42c1ca84cb0b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_68a447cb-bb09-4510-83f0-16601dd965a9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_5a5e5881-1354-4018-aa16-42c1ca84cb0b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_72598e22-9e99-4bbc-b24f-ef7b60707b86" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_5a5e5881-1354-4018-aa16-42c1ca84cb0b" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_72598e22-9e99-4bbc-b24f-ef7b60707b86" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_PerformanceBasedRestrictedStockUnitsMember_e2326395-949c-4e28-9efa-ed4286b3f08b" xlink:href="lifx-20250930.xsd#lifx_PerformanceBasedRestrictedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedStockUnitsRSUMember_72598e22-9e99-4bbc-b24f-ef7b60707b86" xlink:to="loc_lifx_PerformanceBasedRestrictedStockUnitsMember_e2326395-949c-4e28-9efa-ed4286b3f08b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_MarketBasedRestricedStockUnitsMember_fa92fb2f-5613-4cbf-b922-5e44a78a963a" xlink:href="lifx-20250930.xsd#lifx_MarketBasedRestricedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedStockUnitsRSUMember_72598e22-9e99-4bbc-b24f-ef7b60707b86" xlink:to="loc_lifx_MarketBasedRestricedStockUnitsMember_fa92fb2f-5613-4cbf-b922-5e44a78a963a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_TimeBasedRestrictedStockUnitsMember_288deb57-7501-49db-b765-6f36fefe3954" xlink:href="lifx-20250930.xsd#lifx_TimeBasedRestrictedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedStockUnitsRSUMember_72598e22-9e99-4bbc-b24f-ef7b60707b86" xlink:to="loc_lifx_TimeBasedRestrictedStockUnitsMember_288deb57-7501-49db-b765-6f36fefe3954" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_2ffd02be-76d6-4347-8772-4b34e0023d29" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_5a5e5881-1354-4018-aa16-42c1ca84cb0b" xlink:to="loc_us-gaap_EmployeeStockOptionMember_2ffd02be-76d6-4347-8772-4b34e0023d29" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingAxis_7404a989-26f0-4559-92c6-a2418adba3fc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_02f616e9-4b86-4c0a-8e96-47b70e5ec8e7" xlink:to="loc_us-gaap_VestingAxis_7404a989-26f0-4559-92c6-a2418adba3fc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingDomain_7404a989-26f0-4559-92c6-a2418adba3fc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VestingAxis_7404a989-26f0-4559-92c6-a2418adba3fc" xlink:to="loc_us-gaap_VestingDomain_7404a989-26f0-4559-92c6-a2418adba3fc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingDomain_113ed262-7ddc-43c1-a316-ea7d15c27e0a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VestingAxis_7404a989-26f0-4559-92c6-a2418adba3fc" xlink:to="loc_us-gaap_VestingDomain_113ed262-7ddc-43c1-a316-ea7d15c27e0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheOneMember_9fb4c592-30f4-41ff-8b5b-55a3c317bf2c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_113ed262-7ddc-43c1-a316-ea7d15c27e0a" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheOneMember_9fb4c592-30f4-41ff-8b5b-55a3c317bf2c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_04e48c7c-ec1e-439c-bb87-40255ff66da5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_113ed262-7ddc-43c1-a316-ea7d15c27e0a" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_04e48c7c-ec1e-439c-bb87-40255ff66da5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_ca77a8cb-9e7c-4aa2-9176-3d5c62348010" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheThreeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_113ed262-7ddc-43c1-a316-ea7d15c27e0a" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_ca77a8cb-9e7c-4aa2-9176-3d5c62348010" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_df288183-06ed-42e3-8df0-f8fc9437b783" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_71d09928-eed6-4d35-955a-f24ce343e946" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_df288183-06ed-42e3-8df0-f8fc9437b783" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod_363c2274-7b7b-44c5-a09a-df815fb09235" xlink:href="lifx-20250930.xsd#lifx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_71d09928-eed6-4d35-955a-f24ce343e946" xlink:to="loc_lifx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod_363c2274-7b7b-44c5-a09a-df815fb09235" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_f81f1664-ef06-421a-a564-10b157bd06ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_71d09928-eed6-4d35-955a-f24ce343e946" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_f81f1664-ef06-421a-a564-10b157bd06ba" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_68ca6630-e2fb-4ecf-b3ab-916c9b8cb727" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_71d09928-eed6-4d35-955a-f24ce343e946" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_68ca6630-e2fb-4ecf-b3ab-916c9b8cb727" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_b0874f7e-dfcc-4f8c-bbcb-f00ad3ad269a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_71d09928-eed6-4d35-955a-f24ce343e946" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_b0874f7e-dfcc-4f8c-bbcb-f00ad3ad269a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_4e2ad3d5-032b-41a6-bb1a-edc3f107b9c4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_71d09928-eed6-4d35-955a-f24ce343e946" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_4e2ad3d5-032b-41a6-bb1a-edc3f107b9c4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_26fc4152-6019-467d-874f-4de6ce536a95" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_71d09928-eed6-4d35-955a-f24ce343e946" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_26fc4152-6019-467d-874f-4de6ce536a95" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_e4d83a9d-d1b5-4391-b76c-3079d5354034" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_71d09928-eed6-4d35-955a-f24ce343e946" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_e4d83a9d-d1b5-4391-b76c-3079d5354034" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/EquityIncentivePlanScheduleofFairValueAssumptionsDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#EquityIncentivePlanScheduleofFairValueAssumptionsDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/EquityIncentivePlanScheduleofFairValueAssumptionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4ca95c37-31e6-439f-a81b-86b0a07fd8f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_e58bcdeb-f5aa-498d-8807-cc111e166f3b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4ca95c37-31e6-439f-a81b-86b0a07fd8f8" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_e58bcdeb-f5aa-498d-8807-cc111e166f3b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingAxis_7df69be4-4eac-45b8-b0ae-049476638f76" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_e58bcdeb-f5aa-498d-8807-cc111e166f3b" xlink:to="loc_us-gaap_VestingAxis_7df69be4-4eac-45b8-b0ae-049476638f76" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingDomain_7df69be4-4eac-45b8-b0ae-049476638f76_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VestingAxis_7df69be4-4eac-45b8-b0ae-049476638f76" xlink:to="loc_us-gaap_VestingDomain_7df69be4-4eac-45b8-b0ae-049476638f76_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingDomain_e3d6e476-4c10-43b5-bf32-19d212368a5d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VestingAxis_7df69be4-4eac-45b8-b0ae-049476638f76" xlink:to="loc_us-gaap_VestingDomain_e3d6e476-4c10-43b5-bf32-19d212368a5d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheOneMember_c14e2eb2-94a9-49b8-9ad8-4e819731f77b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_e3d6e476-4c10-43b5-bf32-19d212368a5d" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheOneMember_c14e2eb2-94a9-49b8-9ad8-4e819731f77b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_a522d9d1-093f-421d-b436-95541118ca95" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_e3d6e476-4c10-43b5-bf32-19d212368a5d" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_a522d9d1-093f-421d-b436-95541118ca95" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_8707ae1f-2902-4af5-b112-470163d3c05a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheThreeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_e3d6e476-4c10-43b5-bf32-19d212368a5d" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_8707ae1f-2902-4af5-b112-470163d3c05a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_5026c1da-38c8-47e6-8652-485414aeba44" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_e58bcdeb-f5aa-498d-8807-cc111e166f3b" xlink:to="loc_us-gaap_AwardTypeAxis_5026c1da-38c8-47e6-8652-485414aeba44" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_5026c1da-38c8-47e6-8652-485414aeba44_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_5026c1da-38c8-47e6-8652-485414aeba44" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_5026c1da-38c8-47e6-8652-485414aeba44_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_8a9161dd-ddd9-4eae-b4dc-8406acca3feb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_5026c1da-38c8-47e6-8652-485414aeba44" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_8a9161dd-ddd9-4eae-b4dc-8406acca3feb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_MarketBasedRestricedStockUnitsMember_84a0521e-a74b-4885-bb85-876907345b33" xlink:href="lifx-20250930.xsd#lifx_MarketBasedRestricedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_8a9161dd-ddd9-4eae-b4dc-8406acca3feb" xlink:to="loc_lifx_MarketBasedRestricedStockUnitsMember_84a0521e-a74b-4885-bb85-876907345b33" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_632010f9-a102-4af4-8594-13cbfa847b22" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4ca95c37-31e6-439f-a81b-86b0a07fd8f8" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_632010f9-a102-4af4-8594-13cbfa847b22" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_5937b1c7-78aa-4c6b-bbe2-4ba94ae4f18d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4ca95c37-31e6-439f-a81b-86b0a07fd8f8" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_5937b1c7-78aa-4c6b-bbe2-4ba94ae4f18d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_8b8a98f4-3e6f-4e78-82ac-e416dd439bf8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4ca95c37-31e6-439f-a81b-86b0a07fd8f8" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_8b8a98f4-3e6f-4e78-82ac-e416dd439bf8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_ddd2ea70-12df-4c83-8550-b08f8a46ecf2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4ca95c37-31e6-439f-a81b-86b0a07fd8f8" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_ddd2ea70-12df-4c83-8550-b08f8a46ecf2" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/EquityIncentivePlanScheduleofRSUActivityDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#EquityIncentivePlanScheduleofRSUActivityDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/EquityIncentivePlanScheduleofRSUActivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_32df0060-425c-4d9a-9337-7536310176fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3eefc817-0f61-4f96-9b71-39d3c7e24d21" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_32df0060-425c-4d9a-9337-7536310176fa" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3eefc817-0f61-4f96-9b71-39d3c7e24d21" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_261166b7-5600-4589-9caf-b65225ee5e08" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3eefc817-0f61-4f96-9b71-39d3c7e24d21" xlink:to="loc_us-gaap_AwardTypeAxis_261166b7-5600-4589-9caf-b65225ee5e08" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_261166b7-5600-4589-9caf-b65225ee5e08_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_261166b7-5600-4589-9caf-b65225ee5e08" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_261166b7-5600-4589-9caf-b65225ee5e08_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_eb63eb96-3d3a-48f8-be99-ff3fd3e0b281" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_261166b7-5600-4589-9caf-b65225ee5e08" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_eb63eb96-3d3a-48f8-be99-ff3fd3e0b281" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_1efe1aef-2a2f-4b86-ac6e-2915762bdf84" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_eb63eb96-3d3a-48f8-be99-ff3fd3e0b281" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_1efe1aef-2a2f-4b86-ac6e-2915762bdf84" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_7b406183-39fd-498b-a063-7fea59839339" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_32df0060-425c-4d9a-9337-7536310176fa" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_7b406183-39fd-498b-a063-7fea59839339" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_e01b4133-9955-4c8b-8334-bfe3cfb8ffe6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_7b406183-39fd-498b-a063-7fea59839339" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_e01b4133-9955-4c8b-8334-bfe3cfb8ffe6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_3c355949-2c58-4107-8d55-3ec6438d0cd5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_7b406183-39fd-498b-a063-7fea59839339" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_3c355949-2c58-4107-8d55-3ec6438d0cd5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_017e88f1-ea00-4782-a105-688538f243f2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_7b406183-39fd-498b-a063-7fea59839339" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_017e88f1-ea00-4782-a105-688538f243f2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_f56b9539-dbdd-4dd7-9eff-b3e6d94f371c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_7b406183-39fd-498b-a063-7fea59839339" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_f56b9539-dbdd-4dd7-9eff-b3e6d94f371c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_253f44b7-3ab7-4776-98d8-2ada575c4514" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_77b397e4-fae6-4a3a-ae44-9cc4202faa89" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_32df0060-425c-4d9a-9337-7536310176fa" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_77b397e4-fae6-4a3a-ae44-9cc4202faa89" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_5ccc5a31-5ad6-4aaf-998d-f70067555ea0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_77b397e4-fae6-4a3a-ae44-9cc4202faa89" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_5ccc5a31-5ad6-4aaf-998d-f70067555ea0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_be5e8064-6abf-40f9-9448-fb704a48d883" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_77b397e4-fae6-4a3a-ae44-9cc4202faa89" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_be5e8064-6abf-40f9-9448-fb704a48d883" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_7d630754-fe03-4668-8f17-9a1584aea893" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_77b397e4-fae6-4a3a-ae44-9cc4202faa89" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_7d630754-fe03-4668-8f17-9a1584aea893" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_bdec1672-737e-4d06-a82b-b87cfc4adf47" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_77b397e4-fae6-4a3a-ae44-9cc4202faa89" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_bdec1672-737e-4d06-a82b-b87cfc4adf47" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_b1ae149f-ed78-4d28-a869-f2273cc23548" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/EquityIncentivePlanScheduleofStockBasedCompensationExpenseDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#EquityIncentivePlanScheduleofStockBasedCompensationExpenseDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/EquityIncentivePlanScheduleofStockBasedCompensationExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_93ba0f27-38ac-4455-8fb2-5836b7dac689" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_eebf2ab2-9397-4b3f-a4d8-842adf74b51c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_93ba0f27-38ac-4455-8fb2-5836b7dac689" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_eebf2ab2-9397-4b3f-a4d8-842adf74b51c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_c463c6e1-1675-4dc4-a8d4-8f818f1c5a4b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_eebf2ab2-9397-4b3f-a4d8-842adf74b51c" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_c463c6e1-1675-4dc4-a8d4-8f818f1c5a4b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_c463c6e1-1675-4dc4-a8d4-8f818f1c5a4b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_c463c6e1-1675-4dc4-a8d4-8f818f1c5a4b" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_c463c6e1-1675-4dc4-a8d4-8f818f1c5a4b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_8bd6c312-5b0c-4266-be87-c641941a4fe9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_c463c6e1-1675-4dc4-a8d4-8f818f1c5a4b" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_8bd6c312-5b0c-4266-be87-c641941a4fe9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfSalesMember_1352f8df-aa44-473e-9c98-782be05dade1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_8bd6c312-5b0c-4266-be87-c641941a4fe9" xlink:to="loc_us-gaap_CostOfSalesMember_1352f8df-aa44-473e-9c98-782be05dade1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpenseMember_59009f66-335e-4329-8056-922231e9fc2b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ResearchAndDevelopmentExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_8bd6c312-5b0c-4266-be87-c641941a4fe9" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpenseMember_59009f66-335e-4329-8056-922231e9fc2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpenseMember_a47bad1e-1561-4ab7-9f46-d041ad7aebae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_8bd6c312-5b0c-4266-be87-c641941a4fe9" xlink:to="loc_us-gaap_SellingAndMarketingExpenseMember_a47bad1e-1561-4ab7-9f46-d041ad7aebae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember_b7ff4c6e-1670-48da-acc0-ec60f70da2b9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_8bd6c312-5b0c-4266-be87-c641941a4fe9" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpenseMember_b7ff4c6e-1670-48da-acc0-ec60f70da2b9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_f7009cc6-6791-440b-841c-55a440b5cf43" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_eebf2ab2-9397-4b3f-a4d8-842adf74b51c" xlink:to="loc_srt_ProductOrServiceAxis_f7009cc6-6791-440b-841c-55a440b5cf43" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_f7009cc6-6791-440b-841c-55a440b5cf43_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_f7009cc6-6791-440b-841c-55a440b5cf43" xlink:to="loc_srt_ProductsAndServicesDomain_f7009cc6-6791-440b-841c-55a440b5cf43_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_5951ace3-6d0c-4eb0-ae2f-9be7cc5d9d43" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_f7009cc6-6791-440b-841c-55a440b5cf43" xlink:to="loc_srt_ProductsAndServicesDomain_5951ace3-6d0c-4eb0-ae2f-9be7cc5d9d43" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubscriptionAndCirculationMember_9c2e3d6a-3614-49e2-938d-8287f8bddf46" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubscriptionAndCirculationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_5951ace3-6d0c-4eb0-ae2f-9be7cc5d9d43" xlink:to="loc_us-gaap_SubscriptionAndCirculationMember_9c2e3d6a-3614-49e2-938d-8287f8bddf46" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_HardwareMember_3df96b65-71ae-4c08-8451-873d60398234" xlink:href="lifx-20250930.xsd#lifx_HardwareMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_5951ace3-6d0c-4eb0-ae2f-9be7cc5d9d43" xlink:to="loc_lifx_HardwareMember_3df96b65-71ae-4c08-8451-873d60398234" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductAndServiceOtherMember_4b00c872-80cd-4097-af31-589d291f5aa7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductAndServiceOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_5951ace3-6d0c-4eb0-ae2f-9be7cc5d9d43" xlink:to="loc_us-gaap_ProductAndServiceOtherMember_4b00c872-80cd-4097-af31-589d291f5aa7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_6856aeac-1e0f-4668-9f51-8a7474fc2afa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_93ba0f27-38ac-4455-8fb2-5836b7dac689" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_6856aeac-1e0f-4668-9f51-8a7474fc2afa" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/RelatedPartyTransactionsNarrativeDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#RelatedPartyTransactionsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/RelatedPartyTransactionsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_fd3e59f9-bf19-41b4-9aee-45ad0dbcccb8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_fd3e59f9-bf19-41b4-9aee-45ad0dbcccb8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_dab9978b-dc8c-4765-aa1c-7b9459d0b7f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_fd3e59f9-bf19-41b4-9aee-45ad0dbcccb8" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_dab9978b-dc8c-4765-aa1c-7b9459d0b7f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_dab9978b-dc8c-4765-aa1c-7b9459d0b7f8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_dab9978b-dc8c-4765-aa1c-7b9459d0b7f8" xlink:to="loc_us-gaap_RelatedPartyDomain_dab9978b-dc8c-4765-aa1c-7b9459d0b7f8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_608797f5-6390-412f-8844-3d82a9c21b3b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_dab9978b-dc8c-4765-aa1c-7b9459d0b7f8" xlink:to="loc_us-gaap_RelatedPartyDomain_608797f5-6390-412f-8844-3d82a9c21b3b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_2b5edf76-9d8d-4492-8f81-5195a51c38e0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_608797f5-6390-412f-8844-3d82a9c21b3b" xlink:to="loc_us-gaap_RelatedPartyMember_2b5edf76-9d8d-4492-8f81-5195a51c38e0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_15c1601f-c52e-44e9-845d-2110e83d2fc4" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_fd3e59f9-bf19-41b4-9aee-45ad0dbcccb8" xlink:to="loc_srt_CounterpartyNameAxis_15c1601f-c52e-44e9-845d-2110e83d2fc4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_15c1601f-c52e-44e9-845d-2110e83d2fc4_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_15c1601f-c52e-44e9-845d-2110e83d2fc4" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_15c1601f-c52e-44e9-845d-2110e83d2fc4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_1879fd97-f445-4a02-bd82-72501a61f984" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_15c1601f-c52e-44e9-845d-2110e83d2fc4" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_1879fd97-f445-4a02-bd82-72501a61f984" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_HubbleNetworkIncMember_4cad347a-cd20-4a85-b3a5-35cc7782ea9e" xlink:href="lifx-20250930.xsd#lifx_HubbleNetworkIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_1879fd97-f445-4a02-bd82-72501a61f984" xlink:to="loc_lifx_HubbleNetworkIncMember_4cad347a-cd20-4a85-b3a5-35cc7782ea9e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_9b05bab0-0aca-4216-9d71-1870629eb7d5" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_fd3e59f9-bf19-41b4-9aee-45ad0dbcccb8" xlink:to="loc_srt_ProductOrServiceAxis_9b05bab0-0aca-4216-9d71-1870629eb7d5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_9b05bab0-0aca-4216-9d71-1870629eb7d5_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_9b05bab0-0aca-4216-9d71-1870629eb7d5" xlink:to="loc_srt_ProductsAndServicesDomain_9b05bab0-0aca-4216-9d71-1870629eb7d5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_94924657-20ff-4c87-afed-b2bd35257202" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_9b05bab0-0aca-4216-9d71-1870629eb7d5" xlink:to="loc_srt_ProductsAndServicesDomain_94924657-20ff-4c87-afed-b2bd35257202" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_HardwareMember_4d1c0dfc-07fa-457a-a7ce-43e631cbd2fa" xlink:href="lifx-20250930.xsd#lifx_HardwareMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_94924657-20ff-4c87-afed-b2bd35257202" xlink:to="loc_lifx_HardwareMember_4d1c0dfc-07fa-457a-a7ce-43e631cbd2fa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductAndServiceOtherMember_4a3766c7-4e72-48b8-92f7-a66f33a51c2a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductAndServiceOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_94924657-20ff-4c87-afed-b2bd35257202" xlink:to="loc_us-gaap_ProductAndServiceOtherMember_4a3766c7-4e72-48b8-92f7-a66f33a51c2a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_4726f905-185e-4516-ba1b-fc161df307eb" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_fd3e59f9-bf19-41b4-9aee-45ad0dbcccb8" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_4726f905-185e-4516-ba1b-fc161df307eb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_4726f905-185e-4516-ba1b-fc161df307eb_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_4726f905-185e-4516-ba1b-fc161df307eb" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_4726f905-185e-4516-ba1b-fc161df307eb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_98d1b55c-c1ce-487f-868f-b97cfe1f1471" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_4726f905-185e-4516-ba1b-fc161df307eb" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_98d1b55c-c1ce-487f-868f-b97cfe1f1471" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RelatedPartyWarrantMember_11dbbd07-15b0-4655-b479-d106c637c5e2" xlink:href="lifx-20250930.xsd#lifx_RelatedPartyWarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_98d1b55c-c1ce-487f-868f-b97cfe1f1471" xlink:to="loc_lifx_RelatedPartyWarrantMember_11dbbd07-15b0-4655-b479-d106c637c5e2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember_8f539107-1451-4311-b37e-b175d6bb1b79" xlink:href="lifx-20250930.xsd#lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_98d1b55c-c1ce-487f-868f-b97cfe1f1471" xlink:to="loc_lifx_RelatedPartySimpleAgreementForFutureEquitySAFEMember_8f539107-1451-4311-b37e-b175d6bb1b79" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RelatedPartyInvestmentMember_664a475f-4b9d-48a0-8c98-f5374a485955" xlink:href="lifx-20250930.xsd#lifx_RelatedPartyInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_98d1b55c-c1ce-487f-868f-b97cfe1f1471" xlink:to="loc_lifx_RelatedPartyInvestmentMember_664a475f-4b9d-48a0-8c98-f5374a485955" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_5ab89a74-bdcc-4aa1-9743-3916c82178e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsidiarySaleOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_fd3e59f9-bf19-41b4-9aee-45ad0dbcccb8" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_5ab89a74-bdcc-4aa1-9743-3916c82178e8" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_5ab89a74-bdcc-4aa1-9743-3916c82178e8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_5ab89a74-bdcc-4aa1-9743-3916c82178e8" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_5ab89a74-bdcc-4aa1-9743-3916c82178e8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_cc887684-328e-40c2-bb81-b4d03f4d5eee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_5ab89a74-bdcc-4aa1-9743-3916c82178e8" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_cc887684-328e-40c2-bb81-b4d03f4d5eee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IPOMember_7e9a81f6-d4fb-49e8-bef3-79e94561dee4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IPOMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_cc887684-328e-40c2-bb81-b4d03f4d5eee" xlink:to="loc_us-gaap_IPOMember_7e9a81f6-d4fb-49e8-bef3-79e94561dee4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OverAllotmentOptionMember_8f33a942-4d17-4f17-926a-da69a0d2462c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OverAllotmentOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_cc887684-328e-40c2-bb81-b4d03f4d5eee" xlink:to="loc_us-gaap_OverAllotmentOptionMember_8f33a942-4d17-4f17-926a-da69a0d2462c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_0e979d7e-90ab-4509-9836-0f85ab95ecd6" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_fd3e59f9-bf19-41b4-9aee-45ad0dbcccb8" xlink:to="loc_dei_LegalEntityAxis_0e979d7e-90ab-4509-9836-0f85ab95ecd6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_0e979d7e-90ab-4509-9836-0f85ab95ecd6_default" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_0e979d7e-90ab-4509-9836-0f85ab95ecd6" xlink:to="loc_dei_EntityDomain_0e979d7e-90ab-4509-9836-0f85ab95ecd6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_da2013a8-5d24-4387-b522-4b0d9e37df0e" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_0e979d7e-90ab-4509-9836-0f85ab95ecd6" xlink:to="loc_dei_EntityDomain_da2013a8-5d24-4387-b522-4b0d9e37df0e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_SellingSecurityholdersMember_88c4d3a8-4613-4ac4-8b10-50397a38fd64" xlink:href="lifx-20250930.xsd#lifx_SellingSecurityholdersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_da2013a8-5d24-4387-b522-4b0d9e37df0e" xlink:to="loc_lifx_SellingSecurityholdersMember_88c4d3a8-4613-4ac4-8b10-50397a38fd64" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_TechnologyExclusivityAndRevenueSharingAgreementTerm_fa7d0abc-54a5-4345-9731-8e8833c46630" xlink:href="lifx-20250930.xsd#lifx_TechnologyExclusivityAndRevenueSharingAgreementTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_lifx_TechnologyExclusivityAndRevenueSharingAgreementTerm_fa7d0abc-54a5-4345-9731-8e8833c46630" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RevenuePriceCalculationPercentageOverCostOfSales_8f766117-8618-4726-9282-6a30ca4e0463" xlink:href="lifx-20250930.xsd#lifx_RevenuePriceCalculationPercentageOverCostOfSales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_lifx_RevenuePriceCalculationPercentageOverCostOfSales_8f766117-8618-4726-9282-6a30ca4e0463" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_334e6dfa-0200-49bc-9327-34cdbdc59cfc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_334e6dfa-0200-49bc-9327-34cdbdc59cfc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_f9a2444f-0984-4c2d-b31b-fa357b0a3fd3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_f9a2444f-0984-4c2d-b31b-fa357b0a3fd3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_3bf6a980-4d43-4b0f-8722-9eda3e36c77f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_3bf6a980-4d43-4b0f-8722-9eda3e36c77f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_InvestmentInWarrantsShares_43e23883-0f2b-4688-af1f-87cbfe537e5b" xlink:href="lifx-20250930.xsd#lifx_InvestmentInWarrantsShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_lifx_InvestmentInWarrantsShares_43e23883-0f2b-4688-af1f-87cbfe537e5b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermInvestments_08e8e2fe-d448-4c59-8e0b-34c309173043" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_LongTermInvestments_08e8e2fe-d448-4c59-8e0b-34c309173043" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_a2a22fc6-5ccf-43dc-87cb-639aed84be96" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_a2a22fc6-5ccf-43dc-87cb-639aed84be96" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_b4c395bf-43b7-4861-9f02-a3e5ab9f58c7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_b4c395bf-43b7-4861-9f02-a3e5ab9f58c7" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockPricePerShare_bbe1945c-9127-43ef-bbee-abbb7c6d57a0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_SaleOfStockPricePerShare_bbe1945c-9127-43ef-bbee-abbb7c6d57a0" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_071b80ba-cd85-4241-9cd5-ad8c8c1293fc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_071b80ba-cd85-4241-9cd5-ad8c8c1293fc" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfStockIssuanceCosts_ba4391ce-14e9-4869-a561-b4a8c9879c92" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsOfStockIssuanceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_PaymentsOfStockIssuanceCosts_ba4391ce-14e9-4869-a561-b4a8c9879c92" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_dec75753-2654-40c8-ad72-784dc25f8a41" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01874cb4-5790-40c5-85b7-70a8f095ac1e" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_dec75753-2654-40c8-ad72-784dc25f8a41" xlink:type="arc" order="12"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/RelatedPartyTransactionsScheduleofExpensesPaidonBehalfofSellingSecurityholdersDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#RelatedPartyTransactionsScheduleofExpensesPaidonBehalfofSellingSecurityholdersDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/RelatedPartyTransactionsScheduleofExpensesPaidonBehalfofSellingSecurityholdersDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_f161316d-912b-458e-b503-e52b5daa6557" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_e6b0dc68-df7a-4986-9150-9a2404f9ec0f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_f161316d-912b-458e-b503-e52b5daa6557" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_e6b0dc68-df7a-4986-9150-9a2404f9ec0f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_b9c6ae97-11be-4042-a033-93840a0fbda1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_e6b0dc68-df7a-4986-9150-9a2404f9ec0f" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_b9c6ae97-11be-4042-a033-93840a0fbda1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_b9c6ae97-11be-4042-a033-93840a0fbda1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_b9c6ae97-11be-4042-a033-93840a0fbda1" xlink:to="loc_us-gaap_RelatedPartyDomain_b9c6ae97-11be-4042-a033-93840a0fbda1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_2e9aafb8-770b-4cde-860a-87a8563c2e20" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_b9c6ae97-11be-4042-a033-93840a0fbda1" xlink:to="loc_us-gaap_RelatedPartyDomain_2e9aafb8-770b-4cde-860a-87a8563c2e20" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_31f986dd-3ce3-4b57-aff9-b2d2b87f3397" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_2e9aafb8-770b-4cde-860a-87a8563c2e20" xlink:to="loc_us-gaap_RelatedPartyMember_31f986dd-3ce3-4b57-aff9-b2d2b87f3397" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ExecutiveOfficerMember_26091dd9-1a8b-4c13-a084-cd86a764c08b" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ExecutiveOfficerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyMember_31f986dd-3ce3-4b57-aff9-b2d2b87f3397" xlink:to="loc_srt_ExecutiveOfficerMember_26091dd9-1a8b-4c13-a084-cd86a764c08b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_DirectorMember_9e3d04d7-3610-4af1-9015-1b0dd05a48e8" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_DirectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyMember_31f986dd-3ce3-4b57-aff9-b2d2b87f3397" xlink:to="loc_srt_DirectorMember_9e3d04d7-3610-4af1-9015-1b0dd05a48e8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_NonExecutiveEmployeesMember_54e59727-6111-428a-b81d-a4ba24fc6ffd" xlink:href="lifx-20250930.xsd#lifx_NonExecutiveEmployeesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyMember_31f986dd-3ce3-4b57-aff9-b2d2b87f3397" xlink:to="loc_lifx_NonExecutiveEmployeesMember_54e59727-6111-428a-b81d-a4ba24fc6ffd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_OtherRelatedPartiesMember_24f22733-ea0e-4b07-924f-b0f5bd9139c3" xlink:href="lifx-20250930.xsd#lifx_OtherRelatedPartiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyMember_31f986dd-3ce3-4b57-aff9-b2d2b87f3397" xlink:to="loc_lifx_OtherRelatedPartiesMember_24f22733-ea0e-4b07-924f-b0f5bd9139c3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_ExecutiveOfficerAndDirectorMember_de5cf379-b6d2-4910-a141-49b3f82f2d1d" xlink:href="lifx-20250930.xsd#lifx_ExecutiveOfficerAndDirectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyMember_31f986dd-3ce3-4b57-aff9-b2d2b87f3397" xlink:to="loc_lifx_ExecutiveOfficerAndDirectorMember_de5cf379-b6d2-4910-a141-49b3f82f2d1d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_6353c133-197d-4bf5-bf49-b5a17ae25793" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_f161316d-912b-458e-b503-e52b5daa6557" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_6353c133-197d-4bf5-bf49-b5a17ae25793" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/NetIncomeLossPerShareScheduleofAntidilutiveCommonSharesExcludedfromComputationDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#NetIncomeLossPerShareScheduleofAntidilutiveCommonSharesExcludedfromComputationDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/NetIncomeLossPerShareScheduleofAntidilutiveCommonSharesExcludedfromComputationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_b913a501-3527-4992-baac-78f8a18f6926" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_32f0a3cc-43aa-4361-a7b2-af6fc449da62" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_b913a501-3527-4992-baac-78f8a18f6926" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_32f0a3cc-43aa-4361-a7b2-af6fc449da62" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_374fdce5-1b0b-4a11-b38b-1f6ebb80e89e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_32f0a3cc-43aa-4361-a7b2-af6fc449da62" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_374fdce5-1b0b-4a11-b38b-1f6ebb80e89e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_374fdce5-1b0b-4a11-b38b-1f6ebb80e89e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_374fdce5-1b0b-4a11-b38b-1f6ebb80e89e" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_374fdce5-1b0b-4a11-b38b-1f6ebb80e89e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_700e4562-ac31-4d0c-9993-a63163fcca7e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_374fdce5-1b0b-4a11-b38b-1f6ebb80e89e" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_700e4562-ac31-4d0c-9993-a63163fcca7e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_97217117-4962-451f-b48a-f15f6296f713" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_700e4562-ac31-4d0c-9993-a63163fcca7e" xlink:to="loc_us-gaap_EmployeeStockOptionMember_97217117-4962-451f-b48a-f15f6296f713" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_5572fe8b-b311-416e-bd3d-bd099b191b24" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_700e4562-ac31-4d0c-9993-a63163fcca7e" xlink:to="loc_us-gaap_WarrantMember_5572fe8b-b311-416e-bd3d-bd099b191b24" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_fb2c22c3-9d91-414e-affc-ec505620e566" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_700e4562-ac31-4d0c-9993-a63163fcca7e" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_fb2c22c3-9d91-414e-affc-ec505620e566" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtMember_3b3da94b-07f3-4007-a66a-4b943ac501e3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_700e4562-ac31-4d0c-9993-a63163fcca7e" xlink:to="loc_us-gaap_ConvertibleDebtMember_3b3da94b-07f3-4007-a66a-4b943ac501e3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_3aca4221-9062-4ac4-bae8-d581f9d01f1b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_b913a501-3527-4992-baac-78f8a18f6926" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_3aca4221-9062-4ac4-bae8-d581f9d01f1b" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://lifx.com/role/SubsequentEventsDetails" xlink:type="simple" xlink:href="lifx-20250930.xsd#SubsequentEventsDetails"/>
  <link:definitionLink xlink:role="http://lifx.com/role/SubsequentEventsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventLineItems_af28f474-c6a2-45e7-b7e7-78857273e739" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTable_b62e9325-8045-4884-b40a-215b0405dda1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_af28f474-c6a2-45e7-b7e7-78857273e739" xlink:to="loc_us-gaap_SubsequentEventTable_b62e9325-8045-4884-b40a-215b0405dda1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_00d9ce17-fa07-4f53-adc5-81f2fd099b30" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_b62e9325-8045-4884-b40a-215b0405dda1" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_00d9ce17-fa07-4f53-adc5-81f2fd099b30" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_00d9ce17-fa07-4f53-adc5-81f2fd099b30_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_00d9ce17-fa07-4f53-adc5-81f2fd099b30" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_00d9ce17-fa07-4f53-adc5-81f2fd099b30_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_9176f38f-033e-43d0-af26-56e82f04efb3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_00d9ce17-fa07-4f53-adc5-81f2fd099b30" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_9176f38f-033e-43d0-af26-56e82f04efb3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_1c11f5bc-0b55-4d81-a69e-6f015d1b3c72" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_9176f38f-033e-43d0-af26-56e82f04efb3" xlink:to="loc_us-gaap_SubsequentEventMember_1c11f5bc-0b55-4d81-a69e-6f015d1b3c72" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_178bc92c-fe80-480e-81f9-7b9535ddbb13" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_b62e9325-8045-4884-b40a-215b0405dda1" xlink:to="loc_srt_StatementScenarioAxis_178bc92c-fe80-480e-81f9-7b9535ddbb13" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_178bc92c-fe80-480e-81f9-7b9535ddbb13_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_178bc92c-fe80-480e-81f9-7b9535ddbb13" xlink:to="loc_srt_ScenarioUnspecifiedDomain_178bc92c-fe80-480e-81f9-7b9535ddbb13_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_301d51c7-7f96-4d85-a178-26f4a16a0f3f" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_178bc92c-fe80-480e-81f9-7b9535ddbb13" xlink:to="loc_srt_ScenarioUnspecifiedDomain_301d51c7-7f96-4d85-a178-26f4a16a0f3f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioForecastMember_fc25943e-b045-4e0a-ac6b-3c6c2671fb7b" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioForecastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_301d51c7-7f96-4d85-a178-26f4a16a0f3f" xlink:to="loc_srt_ScenarioForecastMember_fc25943e-b045-4e0a-ac6b-3c6c2671fb7b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_7151c3d4-04f3-437e-a06d-ca8124a30281" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_b62e9325-8045-4884-b40a-215b0405dda1" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_7151c3d4-04f3-437e-a06d-ca8124a30281" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_7151c3d4-04f3-437e-a06d-ca8124a30281_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_7151c3d4-04f3-437e-a06d-ca8124a30281" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_7151c3d4-04f3-437e-a06d-ca8124a30281_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2fdf7bac-60f3-4b5c-9493-69dce870fdd5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_7151c3d4-04f3-437e-a06d-ca8124a30281" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2fdf7bac-60f3-4b5c-9493-69dce870fdd5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_NativoInc.Member_315d39cf-4296-4f25-b05a-2d9ee960b897" xlink:href="lifx-20250930.xsd#lifx_NativoInc.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2fdf7bac-60f3-4b5c-9493-69dce870fdd5" xlink:to="loc_lifx_NativoInc.Member_315d39cf-4296-4f25-b05a-2d9ee960b897" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_767d9a73-6c2f-4e64-9a32-fd0e6565c88c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_af28f474-c6a2-45e7-b7e7-78857273e739" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_767d9a73-6c2f-4e64-9a32-fd0e6565c88c" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.xsd#eedm"/>
  <link:definitionLink xlink:role="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrentAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAccruedLiabilitiesCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAccruedLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:to="loc_us-gaap_OtherAccruedLiabilitiesCurrent" xlink:type="arc" order="41"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#IndividualsOnly"/>
  <link:definitionLink xlink:role="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ecd_AllIndividualsMember" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_AllIndividualsMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_lifx_RussellBurkeMember_58dad128-e777-4b19-98b3-ffa48ae4fc38" xlink:href="lifx-20250930.xsd#lifx_RussellBurkeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_lifx_RussellBurkeMember_58dad128-e777-4b19-98b3-ffa48ae4fc38" xlink:type="arc" order="2"/>
  </link:definitionLink>
</link:linkbase>
