Flowkey - The easiest way to learn piano with your iPhone or iPad
Melodics - Melodics is a desktop app that teaches you to play MIDI keyboards, pad controllers, and drums.
HDpiano - HDpiano is the Netflix of Piano Tutorials.
Simply Piano - Fast and fun way to learn piano
Piano Academy - Play your favorite songs
Learn to play Guitar - Learn to play Guitar is an application that is designed to learn or play various guitar tones like Rock, Blues, Jazz, Latin music, and other contemporary styles on Guitar.