iOS 27 battery drain: What to know

iOS 27 has begun rolling out, introducing Siri AI, enhanced Apple Intelligence, AI photo editing, and increased customization for Liquid Glass. Early reactions have been largely positive, but some users have reported their battery draining faster and phones running warmer after updating. According to Apple's support documentation, this is to be expected, not an indication of anything being wrong.

Upon installing a major software update, devices need time to set themselves up in the background, which includes indexing files, downloading new assets, and updating apps. This background activity uses extra power and generates heat, causing battery life and thermal performance to dip temporarily right after an update, as per Apple.

These battery drain issues should improve with future iOS 27 updates. Apple also notes that new features themselves can alter how a phone uses power once setup is completed. For instance, Siri AI may rely more on on-device processing, or expanded Apple Intelligence features could run more frequently, increasing the phone's overall computational work.

Apple asserts that they continue refining this balance between new capabilities and battery life in follow-up updates. This is not a new problem with iOS 27, but rather the expected cost of regular iOS updates, and it is generally not a reason to panic. Apple recently released new AirPods, Apple Watches, and iPhones alongside iOS 27, all of which are available for preorder.