If your idea of a customized case involves more than a custom printed graphic, Case-Mate's ($35) could help bring out your inner Warhol. The case, designed by industrial designer Erik Arlen, consists of six modular sections that stack together to create a slim, protective shell for your iPhone. While the top and bottom pieces have to stay in their respective places, the four middle pieces can be arranged to your liking. You can also order additional color sets for additional creative flair.

The ($28) snaps onto the back of your iPhone and doubles your battery time while adding only a few millimeters of thickness. It prioritizes power consumption, drawing power from its Lithium-ion battery first, before using your phone's battery, in order to maximize the life of the iPhone's internal battery.