Exhibit 10.10
                            LAURUS MASTER FUND, LTD.
                          825 Third Avenue, 14th Floor
                            New York, New York 10022


                                                                 May 28, 2004


SDA AMERICA, INC.
230 Park Avenue, 10th Floor
New York, NY 10169
Attn:  Jay McDaniel


         Re:      Restricted Account: Account Number 2704051693,
         Account Name: SDA America Inc. maintained at North Fork Bank
         (the "Restricted Account").
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     Reference is made to (i) that certain Securities Purchase Agreement,  dated
as of May 28, 2004 (as amended,  modified or supplemented from time to time, the
"Purchase  Agreement"),  by and among  Secured  Digital  Applications,  Inc.,  a
Delaware corporation (the "Parent"),  SDA AMERICA,  INC., a Delaware corporation
(the "Company"),  and Laurus Master Fund, Ltd. (the "Purchaser") relating to the
issuance  of the Series A Preferred  referred  to therein and (ii) that  certain
Restricted Account Agreement,  dated as of May 28, 2004 (as amended, modified or
supplemented  from time to time, the  "Restricted  Account  Agreement"),  by and
among the Company,  Laurus and North Fork Bank (the "Bank").  Capitalized  terms
used but not  defined  herein  shall  have  the  meanings  ascribed  them in the
Purchase Agreement or the Restricted Account Agreement, as applicable.  Pursuant
to the Section 3.2 of the Purchase  Agreement,  the Company is required to place
$6,500,000 in the  Restricted  Account,  and,  subject to the provisions of this
letter, the Purchase  Agreement and any Related Agreement,  maintain such amount
in the  Restricted  Account  for  as  long  as  the  Purchaser  shall  hold  any
outstanding  Series A  Preferred  and to assign the  Restricted  Account for the
benefit of the Purchaser as security for the  performance  of the Parent's,  the
Company's  and  each  of  their  respective  Subsidiaries'  obligations  to  the
Purchaser.

     The Purchaser and the Company desire to clarify certain  aspects  regarding
the  use  of  funds   contained  in  the  Restricted   Account,   and  for  good
consideration,  the receipt and sufficiency of which is here  acknowledged,  the
Company and the Purchaser agree that,  promptly  following any conversion of any
amount of the  outstanding  Series A Preferred  into Common Stock of the Company
(such event, a "Conversion"), the Purchaser shall direct the Bank, pursuant to a
Release  Notice (as defined in the  Restricted  Account  Agreement),  to wire an
amount of funds equal to the corresponding  dollar amount by which the aggregate
Stated  Value of all  outstanding  Series A  Preferred  Shares has been  reduced
pursuant to such a Conversion  from the Restricted  Account to such bank account
as the Company may direct the Purchaser in writing.


     This letter may not be amended or waived except by an instrument in writing
signed by the  Company  and the  Purchaser.  This  letter may be executed in any
number of  counterparts,  each of which shall be an  original  and all of which,
when taken  together,  shall  constitute one agreement.  Delivery of an executed
signature  page of this letter by facsimile  transmission  shall be effective as

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delivery of a manually executed  counterpart hereof or thereof,  as the case may
be. This letter shall be governed by, and construed in accordance with, the laws
of the State of New York.  This letter sets forth the entire  agreement  between
the parties  hereto as to the matters set forth herein and  supersede  all prior
communications, written or oral, with respect to the matters herein.

         If the foregoing meets with your approval please signify your
acceptance of the terms hereof by signing below.

                                     Signed,

                                     Laurus Master Fund, Ltd.


                                     By:   /s/ David Grin
                                     Name:  David Grin
                                     Title:  Director


Agreed and Accepted this 28th day of May, 2004.

SDA AMERICA, INC.

By:  /s/ Patrick Soon-Hock Lim
Name:    Patrick Soon-Hock Lim
Title:   Chairman