Check out this video that compares the performance of the iPhone 6s before and after swapping the battery.
Performance comparison for before/after battery replacement on iPhone 6S. Same phone, different battery.
In December, Apple announced it would be dropping the price of battery replacements from $79 to $29 after it was discovered that iPhones were being secretly slowed down as their batteries aged. Apple touts the slowdown as a feature but it was put in place to avoid unexpected shutdowns on the iPhone 6s; something that doesn't appear to have commonly occurred with earlier generation devices. Rival smartphone manufacturers have since announced that they do not throttle their devices casting doubt on Apple's claim that this is necessary due to the nature of lithium-ion batteries. Already seeded to developers, the upcoming iOS 11.3 software update will show battery health, recommend if a battery needs to be serviced, and allow users to disable throttling. Unfortunately, turning off throttling will not solve the unexpected shutdown problem for users with an iPhone 6/6s.
Currently, there are over 60 class action lawsuits and various investigations opened into the iPhone slowdown. As you can see in the video, there's a notable speed improvement after changing your battery.
Below are links to replacement batteries for each iPhone below for those who want the performance boost of a new battery but can't have Apple perform the replacement for whatever reason (timing, jailbreak, location, etc).
iPhone Battery Replacements:
● iPhone 4G Battery Replacement - $9.49
● iPhone 4S Battery Replacement - $9.49
● iPhone 5 Battery Replacement - $11.99
● iPhone 5c Battery Replacement - $9.99
● iPhone 5s Battery Replacement - $11.99
● iPhone 6 Battery Replacement - $11.49
● iPhone 6 Plus Battery Replacement - $13.49
● iPhone 6s Battery Replacement - $12.49
● iPhone 6s Plus Battery Replacement - $13.49
● iPhone 7 Battery Replacement - $12.49
● iPhone 7 Plus Battery Replacement - $19.49
● iPhone SE Battery Replacement - $14.49
● iPhone 8 Replacement Battery - $29.99
● iPhone 8 Plus Replacement Battery - $29.99
● iPhone X Replacement Battery - $54.49
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