Of the cases in Incase's Systm lineup, Hammer for iPhone 5 ($30) is the least complex, and the least expensive. It's a single-piece rubber case, with Poron XRD inside surrounding the glass portions of the rear panel. The material is also thicker in those areas, adding even more drop protection. Between those bulges, the back is knurled -- the kind of diamond-patterned texture you'll often find on tools. The Sleep/Wake and volume buttons are covered,…
