Apple Inc. (Nasdaq: AAPL) has copped to a battery life issue on the iPhone 4S, saying that it is caused by the iOS 5 operating system and that a fix is on the way.

"A small number of customers have reported lower than expected battery life on iOS 5 devices," Apple said in a statement to AllThingsD. "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."

Some users started to complain to Apple and in online forums about the iPhone 4S draining its battery within a day even with moderate use. Apple had promised that the 4S, launched in October, would offer longer 3G talk time than its predecessor. (See Apple's Latest Is a Faster 3G 'Worldphone' and What Might Shorten iPhone 4S Battery Life?)

If the battery life issue is down to a software bug in the latest operating system, then iPhone 4 and iPad users that upgraded to iOS 5 could also be experiencing battery issues on their devices. LR Mobile would be interested to hear from readers who have upgraded about their experience with battery life.

— Dan Jones, Site Editor, Light Reading Mobile