Defender takes many design cues from OtterBox’s version of the case for the full-sized iPad, and makes one improvement we’ve been requesting for years. Two plastic halves snap around the front and back of the tablet, creating a protective shell. That’s then augmented by a rubber skin that fits flush with the rest of the unit, creating a cohesive case. The back is mostly flat, save for two ridges towards the edges, and we liked the…