The iPhone 4's internal battery does not last very long if you're a power user. Taking video and pictures quickly drains battery life and with all those other features like constant push notifications and using the web, did I forget something? Oh, right, and making calls only makes things worse. If you're finding yourself looking at the red battery indicator all the time, you might want to get yourself a good battery case. We've got you covered with the best battery cases for the iPhone 4. These battery cases were picked based upon their performance and good looks. Surprisingly enough, there are not that many battery cases for the iPhone 4 out there. While there are a few battery cases waiting to be released, here are the top three best battery cases worthy of your iPhone 4.