Learn Music Notes app analytics for April 23

* Input modes: Buttons or Piano * Score history (You'll see quickly how much you improve!) * Practice all clefs (treble, bass, alto, tenor) that you need to master * Three difficulty levels (the harder, the more notes with ledger lines you'll get) * ♯ and ♭ accidentals * Source code of this app is open-sourced at https://github.com/MelvilQ/noten-lernen