When Apple first unveiled the iPhone 5c case, I was surprised that they put holes in the back. If Apple uses less material by putting holes in the case, they use less material and can spend less money on cases. Others may try and claim that the holes make the phone look more aesthetic. Also, the holes on the case are excellent for collecting dust.
However, Flipcase, a new game by Dave McKinney and Stuart Hall, creatively uses these holes to create Connect Four. When you open the game, you simply put your case on the other way so the holes are on the touch-screen side. From there, the game aligns with the holes in the case and you can simply tap where you want to drop a chip.