Now I'm actually thinking about using just taps to move the blocks... How would you suggest doing the rotations?
^_^ ... that's where i was stuck as well, cause there is no screen space for buttons the game area covers almost everything, and my template has even the left side "hold piece" and if i make the gameplay screen smaller i would had to squint my eyes to play which isn't very good.
but i guess swiping up could be a rotation possibility, tapping to move and swipe down to force down the blocks.
the problem with your delay of 0.3 to activate swipe is that it works good on low levels right? cause the speed of blocks is slow, but the moment you are like level 10 or 20 or whenever u increase the speed the blocks, the waiting 0.3 to activate movement fails, that's why i think tetris blitz got it perfect as movement for mobile, the game shows you all the available moves of the current piece in play, and u just select one of the possible moves. I stopped my tetris development there, cause im kinda bad at arrays. ^_^
however if your version has screen space, id just put a rotate button somewhere on the screen. and use the tap to move pieces. but my version doesn't have that luxury ^_^
on my end i have the keyboard controls as secondary and works good so far, and mobile is in the workings for a couple of months now... im stuck at decision making on it.
another reason i stopped development on it, is cause tetris company ltd has a monopoly on the gameplay (including every aspect of it patented, and any clone that is out there is going to be sued whenever it gets any revenue that makes some more than a cup of coffee. you can license the game from them, and clone it, but is probably gonna cost to much to be feasible.)
so im not really sure i want to make a tetris clone anymore for a while now ^_^ and spend my time on marketing it and be then taken down.