Thanks for playing Super Hexagon! If you have any problems with the game, leave a message in the comment box below, and I'll get back to you as soon as possible.
PLEASE READ: The black screen on startup issue is a known problem that I'm looking into! Thank you for your patience - I should have it fixed in an update!
As a temporary workaround until then, maybe people have reported being able to get the game to work by simply deleting it from the phone and reinstalling. Also, try closing down other apps in the background first.