BatterySense helps you track your iPhone's battery power
iPhone 4S users hit by the battery drain problem now have an app that tries to help you get the most out of your current charge.
Updated last week to support Apple's latest iPhone, BatterySense can't conjure up any more power out of your battery. But it does tell you how much time is left on your current charge depending on what you're doing. And it offers some tips and tricks on how to get more out of a single charge.