Diverging considerably in design, iSkin's new Touch Duo ($40) and Pebble ($35) for iPod touch 4G are nonetheless similar in scope of protection. Whereas Touch Duo takes inspiration from iSkin's long-standing series of two-piece Duo cases with hard plastic front shells and opaque soft rubber rear frames, covering everything except for the touch's camera, microphone, screen, headphone port, and speaker, Pebble is a single-piece TPU case with glossy…
