Just before Easter Apple released update of iOS system to 11.3 version for all compatible devices. Size of this update depends on type of device - for example owners of iPhone X will have to download update which has 708MB.
The most important new feature is named Battery Health Tool. Some months ago Apple has been criticized for intentional slowing of their devices to hide poor battery performance, but thanks to this new function we have option to check state of our battery. Phone will show us information if we have to change battery in our device, and also users can choose how their device will work - in optimized way or with full battery power. Apart from this new function we should also mention that update adds new version of ARKit - AR app, which now allows to use new types of surfaces like walls or doors. iOS 11.3 also adds new animojis for iPhone X owners and after update we can finally watch music videos by using Apple Music. Full list of changes is available on Apple's official website.