There are many battery cases out there for the iPhone 4 that come in various sizes to help you get thru your day without the need to plug and wait for your iPhone to charge. Well, Tekkeon has come up with the myPower battery case for the iPhone 4 which comes in a slim form factor and packs a 1,200mAh hot-swappable battery pack. The myPower isn't your ordinary battery case, it has the ability to exchange your drained battery pack for a freshly charged one, that is if you purchase an additional battery module from Tekkeon. So is this sleek and slim battery case really worth your hard earned cash? Read more to find out after the break!