iPhone users (along with regular readers) will know that poor battery life is one of the smartphone's biggest weaknesses. Sure, spend more on a bigger iPhone (the Pro or Pro Max ) and you get a bigger battery, but even this is not enough to satisfy users who live with aniPhone  glued to their hand.

Add to this the fact that iOS updates can greatly affect battery life. Some updates give battery time quite a boost; others take it away.

More often than not, users complain that iOS updates cause a drop in battery life. Sometimes this is real; sometimes, it's just an effect of installing a new operating system and users not giving the platform time to stabilize.

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$429 at Apple

And it seems that there was a problem with the iOS 15.4 update. Apple admits it in the release notes for iOS 15.4.1:

• The battery may drain more quickly than expected after updating to iOS 15.4
• Braille devices may become unresponsive while navigating text or displaying an alert
• Made for iPhone hearing devices may lose connection within some third-party apps

I was curious about that battery drain fix because it felt to me like iOS 15.4 was an actual improvement over the previous release. I've confirmed that this battery boost is seen on other iPhone models too -- ranging from iPhone X toiPhone 12 .

However, my testing of iOS 15.4.1 shows a significant battery life boost.  Up to 30 minutes on my iPhone 13 Pro Max.

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That's a significant increase, so it seems that iOS 15.4.1 does bring with it quite a fix. I'm not sure how much of this problem was brought in with iOS 15.4 and how much of it was "death by the thousand cuts" over time with all the various iOS 15 updates.

The testing I've done seems to suggest that Apple has significantly improved the standby time of the iPhone and that this update causes the iPhone to use less battery when it's not doing much, as opposed to increased efficiencies when it's being pushed hard.

This may account for why battery tests I've seen circulating that involve heavy loads on the iPhone aren't showing much of an improvement.

Whatever the case, it seems that Apple has plugged up quite a significant battery leak with this update.

Should you install it? Well, I'd install it for the battery boost alone, but the security fix for a vulnerability that Apple says "may have been actively exploited" turns this update from a "nice to have" to a must-have."

To update your iPhone or iPad, tap onSettingsand goGeneral > Software Update.

See also

iPhone envy? Here are 3 iOS 17 features already available on Android5 useful iOS 17 features Apple quietly released at WWDC 2023Your iPhone's Wallet app is getting two big iOS 17 updates. Here they areiPhone overheating? Here are 8 potential causes and their solutions

• iPhone envy? Here are 3 iOS 17 features already available on Android
• 5 useful iOS 17 features Apple quietly released at WWDC 2023
• Your iPhone's Wallet app is getting two big iOS 17 updates. Here they are
• iPhone overheating? Here are 8 potential causes and their solutions