iOS 15 battery life vs iOS 14.8 battery life - tested on iPhone 12 and older models

Wonder how iOS 15 battery life fares vs iOS 14.8 battery life? We have the answers for you right here thanks to a YouTuber UltimateiDeviceVids who ran a test between 6 iPhone models to see which one is the clear winner. If you want to know the result first, we can summarize it with the following sentence: if you have an iPhone 8 or later model, you might see slight battery improvements with iOS 15 but no degradation.

iOS 15 battery life vs iOS 14.8 battery life, tested across 6 iPhone models

The test is not scientific by any means and does not use any single app to drain the battery life but it tries to replicate real-world usage scenarios such as streaming videos, using social media apps, playing games, and browsing the Internet. It definitely gives an idea as to what you can expect after upgrading to iOS 15.

The following devices were used to test iOS 15 battery life against iOS 14.8:

iPhone 6s
iPhone 7
iPhone 8
iPhone XR
iPhone 11
iPhone 12

On all devices, the following features were turned off:

True Tone
Night Shift
Auto-brightness

Battery health was 100% on all devices, except for iPhone 8 where it was 99%. The YouTuber also tried to ensure that brightness levels were the same on all iPhones, even though it is not easy to do so with LCD vs OLED displays.

First round: 1 hour of YouTube video streaming, in 1080p quality.

Result: iPhone 6s and iPhone 7 running iOS 15 were behind their iOS 14.8 counterparts by 2% – 4%. Very similar results on other iPhones between iOS 15 and iOS 14.8.

Second round: Instagram usage. Looking at Stories for 10 minutes, and scrolling through posts for 50 minutes.

Result: similar results as the first round.

Third round: 30 minutes of interactive gameplay in Minecraft on each iPhone, and 30 minutes of the game running without any input.

Result: iPhone 6s on iOS 15 froze during testing and required a force restart. However, iOS 15 actually had more battery life on iPhone 8, iPhone XR, iPhone 11, and iPhone 12.

Fourth round: 1 hour of web browsing test that includes loading new webpages and scrolling through them. The first 30 minutes included tested with apple.com, while the second 30 minutes included testing with theverge.com

Result: iPhone 6s on iOS 15 was the first device to die at 3:50. Note that iPhone 6s on iOS 14.8 was at 1% battery life at this stage, so not a lot of difference here. The latter shut down at 3:58. On iPhone 7, iOS 14.8 is ahead by 6%, but on iPhone 8 and later, iOS 15 is ahead in remaining battery percentage.

Fifth round: 30 minutes of gaming with Subway Surfers. The remaining 30 minutes with Subway Surfers running but no input.

Result: a clear trend has emerged by now and iOS 15 is ahead by a few percentage points on iPhone 8 and later, with the biggest lead on iPhone 12 by 6%.

Sixth round: Temple Run: 5 minutes of interactive gaming, 5 minutes of game running without any input.

Result: iPhone 7 on iOS 15 dies at 4:42. iOS 15 maintains lead on iPhone 8 and later.

Seventh round: PUBG: 30 minutes of interactive gameplay, 30 minutes of game running without any input

Result: iPhone 7 on iOS 14.8 dies at 4:52. iPhone 8 on iOS 14.8 dies at 5:10. iPhone 8 on iOS 15 dies at 5:12

With the older phones already shut down, the tests restarted from the first round so that newer iPhones can be benchmarked. In the end, here were the final results:

iPhone 6s on iOS 15 – 3:50
iPhone 6s on iOS 14.8 – 3:58
iPhone 7 on iOS 15 – 4:42
iPhone 7 on iOS 14.8 – 4:52
iPhone 8 on iOS 14.8 – 5:10
iPhone 8 on iOS 15 – 5:12
iPhone XR on iOS 14.8 – 5:39
iPhone XR on iOS 15 – 6:03
iPhone 11 on iOS 15 – 7:28
iPhone 11 on iOS 14.8 – 7:32
iPhone 12 on iOS 14.8 – 8:10
iPhone 12 on iOS 15 – 8:40