What are some alternatives?
When comparing Flowkey and Yousician, you can also consider the following products
Simply Piano - Fast and fun way to learn piano
Synthesia - A fun way to learn how to play the piano.
TuxGuitar - A Multitrack tablature editor and player.
Pianu - Learn to play the piano in your browser.
Melodics - Melodics is a desktop app that teaches you to play MIDI keyboards, pad controllers, and drums.
Skoove - Babbel for learning the piano