Joytunes
Pianu
Touch Pianist
Chroma
Flowkey
Major & Minor Scales
Touch Bar Piano
Melodics
Uberchord Guitar
Fretello
Justin Guitar
Guitar Pro 7
Bohemian Guitars
Fretuoso
Go PlayAlong Tab Player
Moosiko
I've been using Uberchord for a few years by now and it's just amazing. It's all about chords, rhythm and songs. This is no child's game, though, you actually learn how to play. The recognition works for most of my guitars and is borderline crazy, even showing me if I put a finger on the wrong fret. It won't let you just play anything and still pass. They have courses library (they call it learning path) and a pretty large catalog of popular songs. I wish they had solo training, but all in all, highly recommended.
Pianu - Learn to play the piano in your browser.
Fretello - Duolingo for learning how to play guitar
Touch Pianist - Play piano like a pro without playing piano.
Justin Guitar - Over 750 completely free guitar lessons!
Chroma - Welcome to Chroma Cutlery Cnife - Manufacturer of kitchen knives, includes products and contact information.
Guitar Pro 7 - Create, play and share your tabs