Showing up alongside sibling company Hard Candy Cases' ShockDrop, Gumdrop Cases has started shipping its first cases for the iPad Air. Bounce ($35) is a single piece of rubber with a raised tire tread pattern, button coverage, and a hole for the new rear microphone. Drop Tech Series is almost identical to prior cases of the same name, and to ShockDrop. It has the same pattern as Bounce, but incorporates a plastic frame with built-in screen protection…