To replace the battery in your iPhone 6, 6 Plus, 6s, 6s Plus, SE, 7, 7 Plus, 8, 8 and X Plus available to residents of all countries.
Apple has previously confirmed it takes measures to slow down older phones when needed, but said it does this to offset the effect of deteriorating lithium-ion batteries. "We've now extended that feature to iPhone 7 with iOS 11.2, and plan to add support for other products in the future".More news: Seal rips Oprah over ties to Harvey Weinstein
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Apple's practice of slowing down new software on iPhones with older batteries didn't just peeve its customers - it's generated new criticism from Capitol Hill. Last year's update acts as a workaround by slowing down the performance of phones with older and low-charged batteries.
This admission has already led to legal action, with a pair of Los Angeles residents filing a class-action lawsuit.
Apple is reducing the price of an out-of-warranty iPhone battery replacement by $50 - from $79 to $29 - for anyone with an iPhone 6 or later whose battery needs to be replaced, starting in late January and available worldwide through December 2018.
The letter asked Apple to provide details on how it notified consumers about the software update, if any, and if there are any compensations with regards to the batteries affected. That means users could reclaim some of that performance.
If you're still rocking an original 2014-era iPhone 6 Plus, chances are that you're are experiencing reduced performance due to throttling mechanisms that Apple first implemented with iOS 10.2.1. Otherwise, it is probably best to wait and see how things work out over the next few months.