Apple explains why your iPhone may drain faster after updating to iOS 26

Macworld

If you have updated to iOS 26, you have thoughts on the new features and the Liquid Glass look. You may also find, as I did, that your iPhone doesn’t run quite as smoothly as usual. For example, I wanted to send a screenshot via WhatsApp, and it felt like it took forever.

In addition to the sluggish performance, you may have noticed a negative impact on your iPhone’s battery life. Social media is filled with posts similar to xycron.tv on Bluesky:

I love iOS 26 so far but man is it destroying my battery life.— Robin (@xycron.tv) 2025-09-15T23:36:12.068Z

Apple is aware of the issues and has posted a support document explaining what is happening. Here’s what Apple has to say about battery life:

Immediately after completing an update, particularly a major release, you might notice a temporary impact on battery life and thermal performance. This is normal, as your device needs time to complete the setup process in the background, including indexing data and files for search, downloading new assets, and updating apps.

If you’re experiencing sluggish performance in some apps and features, here’s what Apple says:

New features are exciting and help you get even more out of your Apple product, though some may require additional resources from the device. Depending on individual usage, some users may notice a small impact on performance and/or battery life. Apple continually works to optimize these features in software updates to ensure great battery life and a smooth user experience.

The simple fact is that after updating, extensive indexing and optimization processes take place in the background, and these place demands on the iPhone’s processor and memory, hence these apparent slowdowns, which “jolt” themselves back into shape over time. There may also be a few bugs that will only be fixed over time (through further updates).

When your iPhone is obviously affected after performing such a major task, it’s normal to be concerned. Remind yourself that this is typical and things should return to normal after a few hours or even a day or two. If you’re not liking iOS 26 at all, you can downgrade back to iOS 18, but it’s a more complicated installation than the usual method.