Anker® 2400mAh Apple certified external battery Battery Case Cover for iPhone 5S / iPhone 5 spare battery Power Pack Cover (Blue) (Wireless Phone Accessory)
I bought the battery cover for the (active) holiday, in which the iPhone 5 is used as a GPS logger, navigation system etc., so all day intensive draws current. Result: With the battery case, the iPhone also keeps active with multiple power-hungry app