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                                                                 Exhibit 10.11b


                           STOCK PURCHASE AGREEMENT


   This Stock Purchase Agreement (the "Agreement") is entered into as of this
17th day of April 2002, by and between Robert M. Unnold ("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 desires to sell 200,000 shares of Common Stock, $0.01
par value (the "Shares") of the Company 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 $220,000 (the "Purchase Price"), payable to
Seller.

   Subject to the terms of that certain Note dated September 5, 2001, by and
between Buyer and RMU Management LLC (the "Note"), accrued and unpaid interest
on the principal of the outstanding principal of the Note and all interest
accruing through September 5, 2002, equals $33,750. Seller agrees to offset the
Purchase Price by this interest amount resulting in a net purchase price of
$186,250 (the "Net Purchase Price"). Buyer acknowledges that this payment is
full satisfaction of the interest obligation of RMU Management LLC under the
Note.

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Notwithstanding the foregoing, the outstanding principal amount of the Note and
any interest accruing thereon after September 5, 2002 shall remain due and
payable in accordance with the terms of the Note.

   2.  Payment for and Delivery of the Shares.

      (a)  The Net 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 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)  Non-Contravention. The execution and delivery of this Agreement, and
   the consummation by the Seller of the transactions contemplated by this
   Agreement, does not 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

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agreement, indenture or instrument which the Seller 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 or by which any material property or asset of the
Seller is bound.

      (c)   Knowledge of Seller. The Seller has received all materials which
   have been requested by the Seller and has 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, the Company's operating results for the first quarter of
   2002 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, 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

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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 Buyer, 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
   statc 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 Buyer.

      (d)  Reporting Company Status.  The Buyer is registered under Section 12
   of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). The
   Buyer files reports with the Securities and Exchange Commission (the
   "Commission") pursuant to Section 12 and/or 15(d) of the Exchange Act. The
   Buyer has duly filed all materials and documents required to be

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filed pursuant to all reporting obligations under either Section 13(a) or 15(d)
of the Exchange Act (the "SEC Filings"). The Buyer 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.


                             /s/ Robert M. Unnold
                             ----------------------
                             Name: Robert M. Unnold



                                i3 MOBILE, INC.



                    BY: /s/ Edward J. Fletcher
                        ------------------------------------
                        Name: Edward J. Fletcher
                        Title: Senior Vice President Finance

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