MIDIPad DS is an Kaoss Pad-like application for the Nintendo DS. It sends both X and Y positions as MIDI CCs and also a CC that is at 127 when the screen is pressed, and 0 when it’s released. You will need the DSMidiWifi server to use it, that can be found on http://dsmidiwifi.tobw.net/

http://forum.gbadev.org/viewtopic.php?t=13904