Hyper - Extensible, cross-platform terminal built on open web standards.
Flowkey - The easiest way to learn piano with your iPhone or iPad
Windows Terminal - A new command line interface for Windows machines
Yousician - Learn to play music at home, at your own pace
Bidbar - Save and run Terminal commands from the Mac menu bar
Melodics - Melodics is a desktop app that teaches you to play MIDI keyboards, pad controllers, and drums.