Apple’s iOS 11.3 release contains numerous new features & the disable of battery throttling is a widely sought after feature for older devices where users have more control & info on power management … this review by BGR also lists the many additional features in this key release 

iOS 11.3 is here, and you can finally disable battery throttling

iOS 11.3, Apple’s third major update to iOS 11 and the one that everyone’s really been waiting for, is finally here. Anyone running iOS 11 on their iPhone or iPad can go download the over-the-air update right now; as ever, just make sure you’ve got a recent backup, a good Wi-Fi connection, and lots of juice left in your battery. iOS 11.3 brings a bunch of new features to iOS 11 that we’ve broken down below, but there’s really only one thing that most people are looking for: The off switch for Apple’s battery-related performance restrictions.

We’ve had a chance to play around extensively with the new features in iOS 11.3 betas already, so nothing in this new release should come as a surprise. The biggest change is the introduction of several battery health features, which are supposed to make customers happy about Apple’s battery-related performance throttling. The new features are contained within a new “Battery Health” menu, which is under the “Battery” tab on iOS 11.3. The page only really has two fields: Maximum Capacity, which shows what percentage of the original charge your battery can still hold; and Peak Performance Capacity, which tells you if your phone’s performance is being throttled due to the battery.