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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-02-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001135271</issuerCik>
        <issuerName>JAMDAT MOBILE INC</issuerName>
        <issuerTradingSymbol>JMDT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001239372</rptOwnerCik>
            <rptOwnerName>VAIS PAUL A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>APAX MANAGERS INC.</rptOwnerStreet1>
            <rptOwnerStreet2>445 PARK AVENUE</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-02-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3723082</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>27</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Note</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Paul Vais serves as Vice President of Apax Managers, Inc. (Apax Managers, Inc. is the general partner of Apax Excelsior VI Partners, L.P. (&quot;Apax Excelsior VI Partners&quot;). Apax Excelsior VI Partners is the general partner of certain private equity funds, including: (i) Apax Excelsior VI, L.P. (&quot;Excelsior VI&quot;), (ii) Apax Excelsior VI-A C.V. (&quot;Excelsior VI-A&quot;), (iii) Apax Excelsior VI-B C.V. (&quot;Excelsior VI-B&quot;), and (iv) Patricof Private Investment Club III, L.P. (&quot;Patricof Private Investment Club III&quot; and, together with Excelsior VI, Excelsior VI-A and Excelsior VI-B, the &quot;Excelsior VI Funds&quot;), the record holders of the reported shares. Accordingly, Mr. Vais may be deemed to exercise voting or dispositive control over the shares owned of record by the Excelsior VI Funds. Mr. Vais disclaims beneficial ownership of the shares except to the extent of his pecuniary interest.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Paul A. Vais</signatureName>
        <signatureDate>2006-02-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
