as a LiveCode external for MacOSX
Play any Midi notes in real time (no latency) by setting the channel, the pitch, the velocity and the duration - Associate a GM instrument to any of the 16 channels - Manage your Midi connections with physical or logical midi devices - Trigger a LiveCode handler with an incoming Midi event. And more...
Contents of the video are non-contractual
Platforms: MacOSX. (iOS: on demand)
LiveCode commercial edition version 6 or up.
You might find shakobox interesting, too. It's a LiveCode library for playing hypercard tunes on top of sunnYmidi.