what kind of app do you mean, a C/C++ one ?
As I'm not familiar and not informed about C/C++ on the Emulator I can only suggest something that sounds good ^^
* to copy a file or a directory recursively to emulator
adb push <source> <destination>
// You probably need to pushs the apk-files generated by the compiler+tools
* to start emulator
// From my logical view you should be able to select the "runnable" somewhere (if you placed it to the correct place..)
OR do you mean on a real phone
(not the emu)
As we are at the very very beginning of porting and there is no device (just from the google-guys) that is actually capable of running Android, there is probably no solution for that, yet.
I'll inform adsouza of that question, he knows a lot (!) better than me...