Simplism's Silicone Case Set for iPhone 5 ($13) is a surprisingly full-featured package given the low price. The main component is a simple silicone skin, wrapping around the iPhone to protect most of the body -- even including the screen, with a lip over the bezel. All three buttons along the edge are completely covered, while the headphone and Lightning ports are protected with flip-open covers. Also included in the set are protective film, a cleaning…