WASHINGTON - Apple has confirmed the long-held suspicion of some users that it is deliberately limiting the iPhones' processing speed as they age.

According to the company, it has released a feature with the iOS to reduce the processing power of older iPhones in a bid to prevent them from unexpectedly shutting down due to the degrading condition of their batteries.

"Lithium-ion batteries become less capable of supplying peak current demands when in cold conditions, have a low battery charge or as they age over time, which can result in the devices unexpectedly shutting down to protect its electronic components," Apple said in the statement released on Wednesday.

"Our goal is to deliver the best experience for customers, which includes overall performance and prolonging the life of their devices," it added.

Many customers suspect that Apple purposefully slows down the older iPhones to prompt people to buy new ones.

A report released on Monday by Geekbench, an iOS speed test developer, suggested that a simple battery replacement, which costs only about $79, should help the phone function almost like a new one.

"I believe (as do others) that Apple introduced a change to limit performance when battery condition decreases past a certain point," John Poole, developer of Geekbench, wrote in the report.

If the iPhone's performance drops, users are not notified. It may make them think that the slowdown is due to a faulty processor instead of an old battery, the report said.

This will also cause users to think, My phone is slow, so I should replace it, rather than My phone is slow, so I should replace its battery, Poole said.

Xinhua