La Touche Musicale allows you to learn the songs you love on piano. Connect your MIDI keyboard to your device and learn very quickly.
Flowkey - The easiest way to learn piano with your iPhone or iPad
Guitarix - Guitarix is a simple Linux Rock Guitar Amplifier for https://alternativeto.
Melodics - Melodics is a desktop app that teaches you to play MIDI keyboards, pad controllers, and drums.
AmpliTube - Guitar Amp & FX modeling plug-in • Amp, Stomp, Cabinet + Mic, Rack FX modeling
Synthesia - A fun way to learn how to play the piano.
Ampire - State Space Modeled guitar amp/cab/stompbox simulator.