https://www.cnet.com/news/apples-battery-throttling-comes-to-iphone-x-8-and-8-plus-with-ios-12-1/ > In iOS 11.3, Apple gave iPhone users access to its battery management tools, which let people using older iPhones turn on or off the throttling feature (called peak performance capability). In a support page updated Wednesday, Apple said that the feature will come to the iPhone 8, 8 Plus and X with iOS 12.1. But Apple points out that performance management may be less noticeable due to the newer iPhones' more advanced hardware and software. > iPhone batteries naturally degrade as time goes on, and the throttling and unexpected shutdowns are more likely to occur with older iPhones. Since the 8, 8 Plus and X are newer, their batteries are likely to be in better shape than their older iPhone counterparts.