ChordEase lets you play music with difficult chords easily on any MIDI instrument. Though it's primarily intended for jazz, it could be useful for any type of music that modulates frequently. ChordEase ensures that all your notes are harmonically correct, but leaves their sequence and rhythm up to you. In other words, ChordEase handles the rapid music theory calculations, so you can relax and concentrate on groove, feel, and aesthetics.
ChordEase plays songs, which are prepared beforehand. You're expected to stay in sync with ChordEase, and it provides a metronome to facilitate this. Normally you play only in the key of C major, and your notes are then adjusted in real time to fit the song's harmony, using various schemes. Any number of performers can perform through a single instance of ChordEase, using any number of MIDI instruments. Any number of parts can be defined, splits and layers can be set up, and parameters can be changed in real time via MIDI controllers.