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                                                                  Exhibit 10.12a

                            STOCK PURCHASE AGREEMENT

          This Stock Purchase Agreement (the "Agreement") is entered into as of
this 8th day of April 2002, by and between Keystone Venture V, L.P., a limited
partnership, ("Seller") and i3 Mobile, Inc., a Delaware Corporation (hereinafter
referred to as the "Buyer" or the "Company").

                              W I T N E S S E T H:

          WHEREAS, the Seller owns 378,750 shares of Common Stock, $0.01 par
value (the "Shares") of the Company and the Seller individually desires to sell
the Shares owned by each of them to the Buyer, and the Buyer desires to purchase
the Shares from the Seller, all on the terms and conditions set forth herein;

          NOW, THEREFORE, the parties hereto, in consideration of the foregoing
premises and other good and valuable consideration, hereby agree as follows:

          1.  Sale and Purchase of the Shares.

          Subject to the terms and conditions of this Agreement, the Seller
hereby transfers, assigns and sells the Shares to the Buyer, and the Buyer
hereby purchases the Shares from the Seller, at a purchase price of $1.10 per
share, for an aggregate purchase price of $416,625.00 (the "Purchase Price"),
payable to Seller.

          2.  Payment for and Delivery of the Shares.

              (a) The Purchase Price has been paid to Seller in cash by wire
transfer concurrently with the execution hereof; receipt thereof is hereby
acknowledged by Seller.

              (b) Contemporaneously herewith, the Seller is delivering to the
Buyer a certificate or certificates (the "Certificates") evidencing the Shares,
duly endorsed, or

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accompanied by a stock power separate from the certificate duly executed in
blank for transfer, receipt of which is hereby acknowledged by the Buyer.

           3.  Representations and Warranties of the Seller.

           The Seller represents, warrants and agrees to and with the Buyer as
follows:

               (a) Title to Shares. The Seller is the record and beneficial
owner of the Shares, with good and marketable title thereto, free and clear of
all liens, pledges, encumbrances, restrictions, options, rights to purchase
and/or claims of any kind. Other than Seller, no person has any interest in the
Shares owned by Seller.

               (b) Organization. The Seller is a limited partnership duly
organized and validly existing under the laws of the State of Pennsylvania. The
Seller, and its General Partner and such General Partner's Corporate General
Partner have all requisite partnership power and authority to execute, deliver
and perform the terms and provisions of this Agreement and have taken all
necessary and appropriate action to authorize the execution, delivery and
performance of this Agreement. This Agreement has been duly and validly
authorized, executed and delivered on behalf of the Seller, and its General
Partner and such General Partner's Corporate General Partner and constitutes the
legal, valid and binding obligation of the Seller, and its General Partner and
such General Partner's Corporate General Partner enforceable against it in
accordance with its terms.

               (c) Non-Contravention. The execution and delivery of this
Agreement, and the consummation by the Seller, its General Partner and such
General Partner's Corporate General Partner of the transactions contemplated by
this Agreement, does not: (i) result in a violation of the limited partnership
agreements or other organizational documents of the Seller, its General Partner
and such General Partner's Corporate General Partner, or (ii)

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constitute a default under (or an event which notice or lapse of time or both
could become a default) or give to others any rights of termination, amendment
or cancellation of, any material agreement, indenture or instrument which the
Seller, its General Partner and such General Partner's Corporate General Partner
is a party, or result in a violation of any law, rule, regulation, order,
judgment or decree (foreign or domestic and including federal and state
securities laws and regulations) applicable to the Seller, its General Partner
and such General Partner's Corporate General Partner or by which any material
property or asset of the Seller, its General Partner and such General Partner's
Corporate General Partner is bound.

               (d) Knowledge of Seller. The Seller has received all materials
which have been requested by the Seller and have had a reasonable opportunity to
ask questions concerning the Company; and the Company has answered all inquiries
that the Seller has put to them. The Seller represents that it is a
sophisticated investor and has had an opportunity to review and has reviewed the
Company's Annual Report on Form 10-K for the year ending December 31, 2001 and
other such publicly available materials concerning the Company as it has
requested.

          4.   Representations and Warranties of the Buyer.

          The Buyer represents, warrants and agrees to and with the Seller as
follows:

               (a) Organization. The Buyer is a corporation duly organized and
     validly existing under the laws of the State of Delaware. The Buyer has all
     requisite corporate power and authority, and holds all licenses, permits
     and other required authorizations from governmental authorities, necessary
     to conduct its businesses as it is now being conducted or proposed to be
     conducted and to own or lease its properties and assets as they are now
     owned or held under lease. The Buyer has full power and authority to
     execute,

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     deliver and perform the terms and provisions of this Agreement and has
     taken all necessary and appropriate action to authorize the execution,
     delivery and performance of this Agreement. This Agreement has been duly
     and validly authorized, executed and delivered on behalf of the Buyer and
     constitutes the legal, valid and binding obligation of the Buyer,
     enforceable against it in accordance with its terms.

               (b) Non-Contravention. The execution and delivery of this
     Agreement, and the consummation by the Buyer of the transactions
     contemplated by this Agreement, does not: (i) result in a violation of the
     Articles of Incorporation or the By-Laws of the Company, or (ii) constitute
     a default under (or an event which notice or lapse of time or both could
     become a default) or give to others any rights of termination, amendment or
     cancellation of, any material agreement, indenture or instrument which the
     Buyer is a party, or result in a violation of any law, rule, regulation,
     order, judgment or decree (foreign or domestic and including federal and
     state securities laws and regulations) applicable to the Buyer or by which
     any material property or asset of the Buyer is bound.

               (c) Compliance With Law. The Buyer has complied in all material
     respects with all applicable statutes and regulations of the United States
     and of all states, municipalities and applicable agencies and foreign
     jurisdictions or bodies in respect of the conduct of its business and
     operations, and the failure, if any, by the Buyer to have fully complied
     with any such statute or regulation has not and will not result in a
     material adverse effect on the financial condition or results of operations
     of the Company.

               (d) Reporting Company Status. The Company is registered under
     Section 12 of the Securities Exchange Act of 1934, as amended (the
     "Exchange Act"). The Company files reports with the Securities and Exchange
     Commission (the "Commission")

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     pursuant to Section 12 and/or 15(d) of the Exchange Act. The Company has
     duly filed all materials and documents required to be filed pursuant to all
     reporting obligations under either Section 13(a) or 15(d) of the Exchange
     Act (the "SEC Filings"). The Company is listed and traded on the Nasdaq
     National Market and the Company is not aware of any pending or contemplated
     action or proceeding of any kind to suspend the trading of the common stock
     of the Company. The Company's SEC Filings have complied when filed, in all
     material respects, with all applicable requirements of the Exchange Act,
     and did not contain any untrue statement of a material fact or omit to
     state a material fact required to be stated or therein necessary to make
     the statements contained therein not misleading in light of the
     circumstances under which they were made.

          5.  Miscellaneous.

              (a) All agreements and representations and warranties made herein
shall survive delivery of any payment for the Shares and the consummation of the
transactions contemplated herein.

              (b) This Agreement sets forth the entire mutual understanding (and
supersedes any and all understandings, negotiations and/or agreements, written
or oral, not expressly set forth in this Agreement in writing signed by the
parties hereto) between the Seller and the Buyer relating to the purchase of the
Shares hereunder. This Agreement shall be binding upon and shall inure to the
benefit of the Seller and the Buyer and their respective successors and assigns.
This Agreement cannot be modified, changed, discharged or terminated except by
an instrument in writing signed by the party sought to be charged.

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              (c) This Agreement and all of the terms, conditions and provisions
hereof shall be governed by, and shall be construed and interpreted in
accordance with, the laws of the State of Delaware.

              (d) This Agreement may be executed in any number of counterparts,
each of which shall be deemed to be an original, but all of which together shall
constitute one and the same instrument.

          IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first above written.

                                  KEYSTONE VENTURE V, L.P.
                                  By:  Keystone V Partners, L.P.,
                                       its General Partner

                                  By:  Keystone V Management Co., Inc., the
                                       G.P. of Keystone V Partners, L.P.

                                       /s/ PETER LIGETI
                                       ------------------------------------
                                       Name:  Peter Ligeti
                                       Title:  Managing Director,
                                       Keystone V Management Co., Inc.


                                  i3 MOBILE, INC.

                                  By:  /s/ JOHN A. LACK
                                       ------------------------------------
                                       Name:   John A. Lack
                                       Title:  President and
                                               Chief Executive Officer

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