MilkyTracker, the free and open source GPL tracker tool, is now available on Android, thanks to some cross-platform goodness. (Developers: see SDL-lib, which brings a flexible multimedia library to Android and enables a host of multimedia and games, and the NDK, Google’s JNI-based toolset for C/C++ on the platform.)
So, what does this mean? It means a tool already available on an absurd number of platforms (Mac, Windows, Linux, Windows Mobile, and even Amiga), and build-able on more, gets one additional platform. Whether it’s actually useful to have a traditional tracker on your mobile phone is another matter, and that I suspect comes down to whether you’ve either got a) an integrated physical keyboard on your device, or b) an incredible amount of patience. (Or, maybe c) you’re a magician, and have fingers that can operate this interface with touch.) But I do have to try it; I currently run a Droid 2, so the keyboard’s set. I’m curious if someone has a tablet if that works.
The freedom in free software, however, means you’re free to try things out regardless, which I think is a good thing. (The experimentation here is not possible on Apple iOS and Microsoft Windows Phone stores, which forbid software with a GPL license. It’s essentially a legal/political obstacle, not a technical one.)