"Is my iPhone getting slower?"

That is the question many iPhone owners ask themselves whenever a new iPhone is released or they install a new software update on an older iPhone.

While it was long thought to just be speculation, Apple confirmed Wednesday that it's true older models will slow with age, saying that such slowdowns were a deliberate effort to keep older phones running longer as the battery wears down — not a push to buy a new model.

"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 device unexpectedly shutting down to protect its electronic components," Apple's statement said.

Apple software aims to avoid unexpected shutdowns on older phones and this, in turn, can slow the phones. Apple said last year it had released a feature for iPhone 6, iPhone 6s and iPhone SE to help avoid such blackouts. With the recent iOS 11.2 operating upgrade, it's extending that feature to iPhone 7 and plans to add it to future products.

Apple's confirmation comes after Reddit users noticed that their devices were getting slower as the batteries in their iPhones got weaker.

Subsequent tests on older iPhone 6S and iPhone 7 and recent versions of Apple's iOS software by John Poole, founder of the popular Geekbench benchmarking tool for measuring performance on devices, added weight that this was indeed happening.

Some Reddit users reported that replacing the battery in their older phones sped things up.

iPhones, like many recent Android devices, do not have batteries that can be easily replaced by users. Apple charges $79 for a new battery for those without its AppleCare warranty protection, a cheaper cost than several hundred dollars for a new device.

If you're curious about the status of your phone's battery you can download a free app, such as Battery Life from developer RBT Digital, or head into your local Apple Store to get it checked out.

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