Cubasis - Cubasis is Steinberg’s streamlined, multitouch sequencer for the iPad.
Bosca Ceoil - A free, easy to use tool for creating music.
FamiStudio - FamiStudio is very simple music editor for the Nintendo Entertainment System or Famicom. It is designed to be easier to use than FamiTracker, but its feature set is also much more limited.
Zynewave Podium - Podium is a modern digital audio workstation (DAW) for Windows.
SunVox - SunVox is a small, fast and powerful modular synthesizer with pattern based sequencer (tracker).
Renoise - Renoise is a digital audio workstation.