We have both Symbian and J2ME versions. Obviously nearly all Symbian devices can run J2ME applications, but we get a much better user experience from the Symbian version: namely the automatic "Send to <...>" popup and being able to run in the background to upload large files. Basically the development of the application splits into two versions: the Java version and the C++ version. The Java version has both a J2ME version, used for the various phone platforms we run on including SonyEricsson, Motorola and Nokia Series 40, and a J2SE version used for testing. The C++ version runs on various phone platforms including Symbian/UIQ/Series 60, Brew and Windows Mobile, as well as on desktop Windows for testing.