Scosche's new kickBACK sport ($30) straddles the line between a shell and a full case, but comes closer to the latter category given its materials and screen-protecting front lip. It's made of plastic and rubber, a generally winning combination, and though there's protection for the volume buttons, the top and bottom edges are fully exposed, increasing the chances of accidental damage to the device's corners. On the back, you'll find a flip-out kickstand…