iOS update fails to deliver promised iPhone battery improvement

iOS update fails to deliver promised iPhone battery improvement


iOS update does not deliver promised iPhone battery improvement
While some iPhone models saw an increase in battery life with iOS 15.4.1, most did not.
Photo: Ed Hardy/Cult of Mac

Benchmark testing of nine different iPhone models shows that less than half of them experienced any improvement to battery life from the recent iOS 15.4.1 update, despite Apple describing that as a major feature of the new version. More of the handsets saw a decrease instead.

On the devices affected, the drop in battery life is generally small, but it’s nevertheless likely to leave some iPhone users holding off on the update. Which is unfortunate, as iOS 15.4.1 also closes a security hole that Apple says has been actively exploited.

iOS 15.4.1 slightly lowers iPhone battery life

Battery life is critical to any phone user. Even the best device becomes useless when its battery hits 0%. So it’s not surprising that many people were pleased when Apple said iOS 15.4.1 fixed a bug that caused batteries to “drain more quickly than expected after updating to iOS 15.4.”

To test that claim, the battery lives of models from the original iPhone SE to the iPhone 13 running the new version were benchmarked with Geekbench 4 by the YouTube channel iAppleBytes. The results were then compared to the battery lives of those same handsets running earlier iOS versions.

The iPhone 6S, the iPhone 7, the iPhone 8 and iPhone 12 all saw slightly improved battery life when running the latest version. But these are all small increases.

The original iPhone SE, iPhone XR, iPhone 11, iPhone SE 2 and iPhone SE 13 all experienced reduced battery life with iOS 15.4.1. These were mostly slight decreases.

The exception is the iPhone 13, which dropped 5.5%. This is Apple’s handset with the longest battery life, and it still lasts 8 hours on a single charge — more than 90 minutes longer than its closest iPhone competitor. But that’s undoubtedly an unwelcome hit.

Fixing what drain?

It’s not unusual for iOS updates to bring slight changes to battery life, sometime up, sometimes down. These are almost always ignored as they’re unnoticeable outside of benchmark tests. The only reason anyone paid attention with the newest iPhone update is that Apple promised a battery improvement.

Among the changes that went unmentioned is that iOS 15.4 brought slight increases to seven of the nine devices in the Geekbench 4 tests done by iAppleBytes. So it’s not clear what Apple meant when it referred to a battery drain caused buy that update.

Watch the full iAppleBytes video for more details:

But update also fixes a bug

Anyone tempted to pass on iOS 15.4.1 because it’ll decrease their battery life should consider that the update also closes a nasty security hole. Apple warns that with the AppleAVD bug, “an application may be able to execute arbitrary code with kernel privileges. Apple is aware of a report that this issue may have been actively exploited.”

Cupertino doesn’t offer separate iPhone security patches, so the only way to remove this bug is to install iOS 15.4.1.


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