Orfeo is a free, open-source desktop app that turns MIDI files into an interactive piano lesson: notes fall onto a virtual keyboard in real time, keys light up as they play, and you can slow down, loop, transpose, and explore any passage at your own pace. Real-time chord detection, hand-coloured keys, interactive chord and scale explorers, a full mixer, and per-note editing — with a piano roll that looks like it was built this decade.

github.com/Squarebow/Orfeo