VividTracker - Amiga Protracker compatible music tracker for iOS
Figure - Propellerhead creates world-class software products and services that inspire music makers and provide the foundation for a worldwide creative musical community.
OpenMPT - OpenMPT is a popular tracker software for Windows.
keezy - A colorful soundboard. Play with music.
SVArTracker - An advanced music creation tool, tracker, sequencer - an all-in one modular virtual studio
Splice - Music creation, collaboration, and sharing made simple.