Apple released iOS 11.3.1 to the general public to address most of the bugs found in iOS 11.3. Even though the new update fixes several bugs, it also comes with a few bugs of its own.
Unfortunately, users who have upgraded to iOS 11.3.1 have noticed that their batteries discharge in 10 minutes, while other have said that the battery percentage drops every second. It seems as if the new battery health monitor feature is causing the battery to drain faster than it should.
I just saw my iPhone battery drop from 58% to 7% in 3 minutes. @Apple iOS 11.3.1 is awful.
— Nelson (@look_its_nelson) April 29, 2018
iOS 11.3.1 also has a bug that is preventing iPhones from charging properly. Many users have been reporting that their iPhones get extremely hot while the device is charging.
@AppleSupport since upgrading IOS 11.3.1 my phone just keeps getting really fuckin hot and my battery dies so fast, even when my phone is locked ???? help ????
— ray (@imyselffamhell) May 1, 2018
Shortly after the release of iOS 11.3.1, Apple stopped signing iOS 11.3 which means users will no longer be able to downgrade to iOS 11.3 or any previous version of iOS 11.2. Apple stops signing older versions of its software so that users will use the latest version of the iOS.
Source: Phone World