<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-02-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001361983</issuerCik>
        <issuerName>ORBCOMM Inc.</issuerName>
        <issuerTradingSymbol>ORBC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001368678</rptOwnerCik>
            <rptOwnerName>Eisenberg Jerome B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ORBCOMM INC.</rptOwnerStreet1>
            <rptOwnerStreet2>2115 LINWOOD AVENUE, SUITE 100</rptOwnerStreet2>
            <rptOwnerCity>FORT LEE</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07024</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Unit (Time Vested)</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2011-02-01</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15759</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by Cynthia Eisenberg</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>981095</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Appreciation Right</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>11</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>95187</value>
                    <footnoteId id="F3"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>95187</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Appreciation Right</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.96</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>100000</value>
                    <footnoteId id="F4"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>100000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2.325</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2005-03-31</value>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <value>2014-02-17</value>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>166667</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>166667</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2.775</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2005-12-31</value>
                <footnoteId id="F6"/>
            </exerciseDate>
            <expirationDate>
                <value>2014-02-17</value>
                <footnoteId id="F6"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>33334</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33334</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.375</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2006-12-31</value>
                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <value>2014-02-17</value>
                <footnoteId id="F7"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>33334</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33334</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.26</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2006-12-31</value>
                <footnoteId id="F8"/>
            </exerciseDate>
            <expirationDate>
                <value>2014-02-17</value>
                <footnoteId id="F8"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>33334</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33334</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2.325</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2007-12-31</value>
                <footnoteId id="F9"/>
            </exerciseDate>
            <expirationDate>
                <value>2014-02-17</value>
                <footnoteId id="F9"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>33334</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33334</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each time vested Restricted Stock Unit (&quot;RSU&quot;) represents the right to receive one share of common stock. The number of RSUs was determined by dividing $30,000 by the closing price of ORBCOMM Inc. common stock on February 1, 2011 of $3.00 per share. The RSUs vest on January 1, 2012.</footnote>
        <footnote id="F2">Includes 49,778 shares underlying time vested RSUs that vested on January 1, 2009 and 36,525 shares underlying performance vested RSUs that vested in March 2009.</footnote>
        <footnote id="F3">Each Performance Vested Stock Appreciation Right (&quot;PV SAR&quot;) represents the right to receive a payment measured by the increase in the fair market value of one share of common stock from the date of grant of the PV SAR to the date of exercise of the PV SAR. One-third of the PV SAR awards vested based on the achievement by the employee and/or the Company of certain performance targets for each of the fiscal years 2006, 2007 and 2008. The PV SARs expire in October 2016 and have an exercise price equal to the initial public offering price of $11.00 per share. In April 2007, 43,500 PV SARs vested based on achievement of certain 2006 performance targets and 6,500 PV SARs lapsed unvested. In March 2008, 15,000 PV SARs vested based on achievement of certain 2007 performance targets and 35,000 PV SARs lapsed unvested. In March 2009, 36,687 PV SARs vested based on achievement of certain 2008 performance targets and 13,313 PV SARs lapsed unvested.</footnote>
        <footnote id="F4">Each Time Vested Stock Appreciation Right (&quot;TV SAR&quot;) represents the right to receive payment measured by the increase in the fair market value of one share of common stock from the date of grant of the TV SAR to the date of exercise of the TV SAR. 50,000 of the TV SAR awards vested on December 31, 2008 and 25,000 of the TV SAR awards vested on each of December 31, 2009 and December 31, 2010. The TV SAR awards expire in March 2018 and have an exercise price of $4.96 per share, the closing price of the common stock on the grant date.</footnote>
        <footnote id="F5">166,667 Options were issued on February 17, 2004 and became fully vested on March 31, 2005. The Options expire on February 17, 2014.</footnote>
        <footnote id="F6">33,334 Options were issued on February 17, 2004 and became fully vested on December 31, 2005. The Options expire on February 17, 2014</footnote>
        <footnote id="F7">33,334 Options were issued on February 17, 2004 and became fully vested on December 31, 2006. The Options expire on February 17, 2014.</footnote>
        <footnote id="F8">33,334 Options were issued on February 17, 2004 and became fully vested on December 31, 2006. The Options expire on February 17, 2014.</footnote>
        <footnote id="F9">33,334 Options were issued on February 17, 2004 and became fully vested on December 31, 2007. The Options expire on February 17, 2014.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Christian Le Brun, by power of attorney</signatureName>
        <signatureDate>2011-02-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
