I'm researching developing a small mobile application and am unsure which technology to use. Initially, it will be very simple updating a few fields in an invoice table with MSSQL as the backend. Blackberry, Windows Mobile, Web App ? I would like to use the MM framework with the web service connection as the backend. The application will eventually become more complex adding credit card payments etc... I would like to support more than one device. Any suggestions on which technologies to use will be appreciated.