The row over Apple's decision to throttle the performance of iPhones has resurfaced after the firm revealed its latest iOS update brings the controversial feature to iPhones bought just a year ago.
The firm, which was hit by a huge customer backlash after the 'batterygate' throttling was first revealed, has previously said there was no need to bring the 'performance management feature' to its latest phones.
However, the release notes for iOS 12.1, released on Tuesday, revealed Apple has brought the controversial feature to the iPhone X, iPhone 8 and iPhone 8 Plus - which were released just a year ago.
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In iOS 12.1, Apple has brought its controversial throttling feature to the iPhone X (pictured), iPhone 8 and iPhone 8 Plus, despite previously saying there was no need for it on its latest phones
To check if Apple is throttling your phone, go to Settings Battery Battery Health.
It will show the exact amount of degradation on your battery, and it will tell you if it's being throttled.
If it is, an option to turn off the feature should be displayed.
The row led to many accusing Apple of 'built-in obsolescence' that effectively forced users to buy a new phone.
As batteries in all phones and gadgets age, they become less effective.
Meanwhile, as software becomes more advanced, it puts more of a strain on the battery and processor as the phone ages, and it come cases, this can cause phones to simply shut down.
Apple's performance management feature throttles some system components, such as the CPU and the GPU, as the battery degrades over time to prevent the device from randomly shutting down.
Previously, this was an automatic feature in every iPhone, but following massive outrage from users, Apple began giving them the option to turn it off in iOS 11.3.
But Apple admitted in the iOS 12.1 release notes that the performance management feature will be turned on for its latest iPhone models - many of which users have only owned for a year or less.
'Additionally, users can see if the performance management feature that dynamically manages maximum performance to prevent unexpected shutdowns is on and can choose to turn it off,' Apple states.
Apple's performance management feature throttles some system components, such as the CPU and the GPU. The firm began giving users the option to turn it off with iOS 11.3
'...This feature applies to iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPhone SE, iPhone 7, and iPhone 7 Plus.
'Starting with iOS 12.1, iPhone 8, iPhone 8 Plus and iPhone X include this feature, but performance management may be less noticeable due to their more advanced hardware and software design,' the firm added.
However, the firm maintains that the impacts of throttling may be 'less noticeable' on the iPhone 8, iPhone 8 Plus and iPhone X.
That's because these models have more advanced hardware and software that gives a more accurate reading of battery life and which apps are draining the battery the most.
To check if Apple is throttling your phone, go to