I want to implement an API on Windows mobile 6 device as the following:
1- device is a PDA with Windows mobile 6.1 and a nummber of Aplications are installed it.
2- customer wants when one of the Aplication is new released (or all) the user can get the application directly (remotly) from a server (other remote computer), with out connecting the device to a computer.

The question is:
- how i can implement this application for remote file access?
- which file tranport protocol can i use?
- is any application customer can buy and install it in the devices?
- is any Mobile FTP to use in Windows mobile? which one is best?
- is any other tool for file transfer?

othe info: I should develop this application in .NET compact and C#. the transfer files shall be either .CAP, .Sys, or .exe.

Thanks in advance for helping
/Sahand