It implements the user interface of littlesounddj, a very famous tracker for the Gameboy platform that has been tried and tested by many users over the years, leading to a little complex but yet extremely efficent way of working.
Piggy currently supports 8 monophonic 16Bit/44.1Khz stereo sample playback channels. Additionally, the program can drive MIDI instruments (with the gp32 and gp2x a custom MIDI interface is required).