The controls were a concern of mine. I needed the player to be able to turn in place, so I went back and forth between the "tank" control scheme and one in which you'd have to double tap to move in a different direction. Perhaps I chose poorly!
Thanks for the note about not being sure which button to use on the title screen, too. I had hoped my writeup on the page would avoid that frustration, but some "on-screen" guidance may have been better.