SunVox is a small, fast and powerful modular synthesizer with pattern-based sequencer (tracker).
It is a tool for those people who like to compose music wherever they are, whenever they wish. On any device. On any system.
And it's free for most of the systems, except the Android and iOS.
Key features:
highly optimized synth algorithms, flexible architecture; SunVox works on a variety of devices with different CPUs;
supported systems:
Windows;
macOS (10.6+);
Linux (x86, x86_64, ARM (Maemo-devices, Raspberry Pi, PocketCHIP, etc.), ARM64 (PINE64 etc.));
iOS (7.0+);
Android (2.3+);
Windows CE (including Pocket PC and Windows Mobile; ARM only);