iOS 11.3 will let you disable battery-related throttling

 This spring iPhone 6 (and later) users will regain control over the performance of their phone. iOS 11.3 will add more detailed info on the battery’s health and whether or not the chipset is throttled. If it is, there will be an option to return it to full speed.



This new version of iOS came out in beta today, but the battery toggle has not been implemented yet. It will be added in a later beta release.
Some of the other additions in iOS 11.3 are available, though. New animojis for one: dragon, bear, skull and lion bring the total of available characters to 16.
Business Chat will go into beta when iOS 11.3 comes out. It allows consumers to interact with businesses like Discover, Hilton, Lowe’s and Wells Fargo. You can chat with a representative, make an appointment and even make a purchase with Apple Pay.

Business Chat (new in iOS 11.3) will connect users with businesses

ARKit will be bumped up to version 1.5, allowing it to recognize vertical surfaces as well (walls, posters on those walls, doors, etc.). It will also do a better job at tracking irregular horizontal surfaces (say, a round table).
Health Records will show your data from hospitals and clinics, organized in one easy to browse view. You’ll also receive regular notifications with your lab results. All data is encrypted and protected with a passcode.

Health Records show information from hospital and clinics and will notify you when lab results arrive

A few more features include music videos in Apple Music, Advanced Mobile Location for emergency services.