TonesynthDS is a virtual synth/sequencer for NDS.

Thanks to http://www.nintendomax.com/index.php?topic_id=10733 or http://www.dcemu.co.uk/vbulletin/showthread.php?p=2148276451 or http://www.tehskeen.com/forums/showthread.php?threadid=14905 or whoever got it first 🙂

http://ndscomposer.blogspot.com/2009/10/tonesynthds-v021-first-testrelease.html