Apple has finally admitted to what many have suspected for years: it deliberately slows down old iPhones with new iOS updates.

The technology giant acknowledged the shady practice after tech bloggers demonstrated that older phones experience significant slowdowns when using the newest operating systems.

But Apple insists the slowdown is simply meant to prioritize battery life over processing speed in old phones - not to drive users to frustration so they upgrade their devices, as critics have suggested.

Apple says it introduced the slowdown last year to compensate for a gradual decay in the lithium-ion batteries used in most smartphones, which become weaker over time. Essentially, new versions of iOS require more power to operate, so an Apple phone will slow down its central processing unit (CPU) when trying to draw more power from a dying battery.

Technology analyst Carmi Levi called it an “unprecedented” revelation from Apple. “This just confirms what we already knew,” Levi told CTV News Channel on Thursday. “It’s been one of those industry secrets. Everyone suspected it but nobody ‘fessed up.”

He added that while some have been quick to condemn Apple and declare their intent to swap to another smartphone-maker, the reality is everyone is doing the same thing.

“This is an industry-wide problem” Levi said.

Apple’s acknowledgement came after a handful of technology writers used third-party apps to record the speed of older iPhones running different generations of Apple’s iOS.

One user observed his iPhone 6 CPU running at less than half its default speed with an old battery, only to return to its factory setting speed after a battery change.

Apple defended its decision to prioritize power over performance in a statement to tech writer Rene Ritchie.

“Our goal is to deliver the best experience for customers, which includes overall performance and prolonging the life of their devices,” Apple said. The smartphone maker said it slows devices down to avoid sudden shutdowns when a phone’s power demands “peak” and the battery is unable to handle it. “Lithium-ion batteries become less capable of supplying peak current demands when in cold conditions, (when they) have a low battery charge or as they age over time,” Apple said.

The slowdown was first put into effect for the iPhone 6, 6S and SE last year “to smooth out the instantaneous peaks,” according to Apple. “We’ve now extended that feature to iPhone 7 with iOS 11.2, and plan to add support for other products in the future.” Older Apple devices do not support the current version of iOS, and so are not affected by the same built-in slowdown.

In other words, the best way to prolong the life of your smartphone is either to avoid updating it, or to get a battery replacement as soon as you notice it slowing down.

The revelation irked many users, with some calling for Apple to offer customers more choice in the matter, such as the option to prioritize performance instead of battery life.

“It’s incredibly convenient that Apple has put this feature in (and) didn’t bother telling us until after everybody complained,” Levi said.

Apple’s current iOS, 11.2, debuted earlier this month, introducing several new fixes and performance improvements that just might be enough to push your old phone’s battery over the edge – right on time for Christmas.

But while buying a new battery might be enough to add a year or two to your smartphone’s lifespan, Levi says it’s eventually worth it to upgrade so you can stay on top of the latest apps and security updates.

“Over time, the hardware stays the same but the software gets bigger,” he said. “Eventually there’s nothing you can do. You head to the store and you buy another one because that’s just the way it is.”