HapticKey - Trigger haptic feedback when tapping Touch Bar
Flowkey - The easiest way to learn piano with your iPhone or iPad
TouchBar for your old MacBook - Use Touch Bar on an iPad through USB connection
Yousician - Learn to play music at home, at your own pace
Touch Bar Nyancat - Nyancat on your MacBook Pro's Touch Bar #innovation
Melodics - Melodics is a desktop app that teaches you to play MIDI keyboards, pad controllers, and drums.