For the most part, Clamcase looks identical to its predecessor: it’s a mostly matte-finished hard plastic shell that opens like a clam—or laptop—to reveal an iPad holder on the top and a keyboard on the bottom. The keys are laid out the same way, the hinge is the same, and even the rubber feet on the bottom are the same. The big difference is the shell that holds the tablet in place. Because hard plastic doesn’t give like rubber…