RapidComposer - MusicDevelopments RapidComposer: Music Prototyping and Automated Composition Software
Captain Chords - Write chord progressions in your favorite DAW
Instachord - MIDI Processing Plugin that helps you play chords and chord progressions faster and easier.
Cthulhu - VST MIDI-FX plugin for harmonic inspiration
AutoTheory - MIDI FX songwriting tool to easily create professional scores over any chord progression
Helio Workstation - Cross-platform lightweight speed-painting tool for creating music.