Google experiment accidentally turned on battery saver for users on Android Pie

Earlier today, many users running Android Pie noticed that battery saver had randomly turned on for them, even if their devices were fully charged. Going into settings, the users noticed that battery saver was set to turn on automatically at 99% battery, which is strange since the slider only allows users to choose a battery saver trigger threshold as high as 75%. Thousands of users on Reddit’s /r/GooglePixel, /r/Essential, and /r/Android subreddits noted the issue and the only thing in common between all the affected devices was that they ran Android Pie. Now, a Google representative has confirmed on Reddit that the battery saver issue was because of an internal experiment that was rolled out to more users than they had intended.

“Hi all, some of you may have noticed that battery saver turned on automatically today. This was an internal experiment to test battery saving features that was mistakenly rolled out to more users than intended. We have now rolled battery saver settings back to default. Please configure to your liking. Sorry for the confusion.” – /u/PixelCommunity on Reddit

If you thought you were going crazy this morning, you’re not alone. A lot of users were surprised when they discovered their device was in battery saver mode. My OnePlus 6 running Android Pie was affected, a LineageOS developer building Android Pie for the Xiaomi Mi 6 was affected, and other devices like the Nokia 7.1 Plus were also affected. Unsurprisingly, devices with the “semi-GSI” (Android 9 port based on the Google Pixel XL system image) were also affected by this bug.

Google is able to run device experiments via system apps like Device Health Services and Google Play Services, but usually, you won’t notice them because you’re not supposed to notice them. If you’re at all surprised by the fact that Google is able to make these kinds of settings changes via a server-side experiment, check out the permissions that Google Play Services has and you’ll see that it’s a lot more powerful than you might have thought at first.