Not sure if it’s just me and my phone (Android A20) but the menu icons are only partially on screen, I had to tap the very edge of the screen to use them. Unfortunately I can’t attach a screenshot. Also, like SPCTR, when I quickly switched over to my browser to check which key on a piano is C, I had to restart. Speaking of the piano puzzle, I think it could be improved by just having a little “C” marking on the C key in the octave that should be played, because the piano has multiple octaves.