This iPhone case made from duralumin—an aluminum alloy used in aircraft construction—features a camera mount that can fit specially made interchangeable external lenses. Available lenses, sold separately, include close-up, wide-angle, and fish-eye. The Quattro has a calfskin leather backing with several different designs, such as lizard and crocodile. While the Quattro may be a good case for taking pictures with your iPhone, it's not so great for other purposes. The manufacturer warns that the aluminum case may interfere with the iPhone's reception of Wi-Fi, GPS, and cellular signals.