Apple is to release a software update to its iOS 5 operating system, acknowledging customer complaints on the performance of the iPhone 4S battery.
"A small number of customers have reported lower-than-expected battery life on iOS 5 devices," Apple said. "We have found a few bugs and we will release a software update to address those in a few weeks."
A rash of complaints on the phone's short battery life have cropped up in online forums. It has also affected some of the iPad tablet computers.