iCopter is another example of a hugely addictive game that only uses a single button. You control a helicopter flying through a cave that gets smaller and smaller in size. Well, you don’t so much control it as hold your finger on the screen to keep it airborne. This makes for a smooth gameplay experience which will test your concentration and reflexes. Along the way you have to avoid obstacles while collecting coins and power-ups. There is little more to do in iCopter than try to get as high a score as possible, but the challenging gameplay will keep you instinctively coming back for more.