1. A mobile electronic device, comprising: at least one coprocessor having dynamic functionality; a host processor system including a cross compiler for converting code into unlinked executable target processor code and a cross linker for converting the unlinked target processor code into linked executable target processor code, said host processor executing: said cross compiler receiving source code and compiling said source code into a native code routine for a target coprocessor selected from said at least one coprocessor; and said cross linker resolving addresses in said native code routine and downloading said native code routine to said target coprocessor; and circuitry for communicating said downloaded native routine between said host processor system and said target coprocessor for controlling the functionality of said target coprocessor.