Heat Synthesizer is available at Samsung Apps and supports Soundcamp, the new realtime audio sequencer available for Samsung devices as part of the new Samsung Professional Audio system.

Samsung Professional Audio supports low latency playback and inter-app audio- & MIDI communication as well as support for a high variety of USB interfaces.

Soundcamp will be officially presented at the Samsung DevCon 2014:

http://samsungdevcon.com/soundcamp-and-samsung-professional-audio

At the moment, Soundcamp supports the new devices Note 4 and Note Edge. Older Samsung devices might be supported as well in the future.