December 30, 1999


ComVest Capital Management LLC
830 Third Avenue
New York, NY  10022

         Re:      Advancement of Funds

Gentlemen:

     Reference is made to that certain Commitment Letter dated December 30, 1999
(the "Letter")  between  ComVest  Capital  Management LLC  ("ComVest")  and U.S.
Wireless  Data,  Inc. (the  "Company").  Capitalized  terms used herein  without
definition are used as defined or referred to in the Letter.

     This  letter is to  confirm  that I, as a lender,  will  subject to ComVest
first having funded $195,000 under the Letter, advance funds to the Company in a
proportionate  amount to that funded to the  Company by ComVest  pursuant to the
Letter.  For each $1 advanced by ComVest after such initial $195,000 is advanced
I will advance a fraction of such dollar,  the numerator of which is 100 and the
denominator of which is 805.

                                                 Sincerely,


                                                 /s/ Dean Leavitt
                                                 Dean Leavitt