iPhone 4S has a major battery problem. Lots of iPhone 4S users have been complaining about their battery life. It was found that the device was draining 10% of charge every hour, even in the standby mode. Even when special features like Location Services and Siri were turned off.
Finally Apple said that they are aware about a number of bugs in iOS 5 that will affect the battery life negatively, and that a fix is coming.
“We have found a few bugs that are affecting battery life and we will release a software update to address those in a few weeks.”
Apple has made iOS 5.0.1 available to developers for testing. So we can hope soon Apple will release the iOS 5.0.1 update.