Well this could be a problem.  iPhones are fairly sturdy but the odds of users stabbing their fingers straight through the screen just skyrocketed today with the release of Thumper: Pocket Edition on iOS.  The shiny chrome bug has been traveling down the groove for a while now on consoles and PC, but mobile has been safe from its audio onslaught.  That's over with as of right now, though, and the heavy rhythms and brutal gameplay of Thumper is ready to endanger phones and iPads everywhere.

Which sounds all kinds of dramatic but seriously, the tone of the game left me with a sore thumb for a week after reviewing the original version just because the concentration it demands translates to a very heavy press on the single action button.  The simple nature of the controls does mean it translates nicely to touch-screen, though, tapping to thump the glowing squares and swiping and holding for turns, jumps, and ramming through barriers.  It only took a couple of minutes practice to get up to speed with the new system, at which point I promptly started trying to pull off the fancy moves and died.  Thumper is as unforgiving as it is darkly beautiful, and now you can play it on the go.  Just remember to be careful while doing it.