After spending some time with this game (on a phone emulator) I think it's becoming one of my top 3 Tetris games ever!
I did note some stuff that could make it better, at least in my opinion:
It would be nice to have the lines recorded in the hiscore as well (at the end), to know how many lines one has cleared.
Besides disabling diagonal presses, disabling hard drop would be really useful, at least when playing on a touch screen. If playing with a controller, I understand that this might not have much use.
Also, sometimes the music lags, no matter the song, I don't know why it happens. The game runs normally but the audio stutters