iOS updates are a rollercoaster of ups and downs. One moment you're languishing in an oasis of calm, the next thing you know, you're fighting with battery life issues and loads of bugs.

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This is what iOS 15.3 was like. It was better than iOS 15.2 but worse than iOS 15.2.1.

So, when Apple pushed out iOS 15.3.1, I installed it rather gingerly. Because this contained a security patch for a serious and actively exploited vulnerability, it's not like I had much of a choice but to install it (unless I was feeling lucky, which I wasn't, to be honest).

The release notes mention a fix for a security vulnerability and an issue with Braille displays, so I wasn't hopeful of any other fixes.

Turns out I was wrong.

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I don't mind being wrong on some things.

As seems to have become the case with iOS updates, Apple rolls unspecified bug fixes into its updates now and doesn't bother to list them.

iOS 15.3.1 is like a breath of fresh air.    

Battery life is improved.

The app sluggishness is gone.

Even better, things that were previously fixed -- like the hotspot being twitchy and Bluetooth being unreliable -- haven't been rebroken.

That's quite a surprise because it's felt like Apple has been playing whack-a-mole with these bugs for a few updates now. Sometimes these bugs are there; other times, they're gone.

Maybe they're finally gone for good.

Battery life is noticeably improved with this update. Either that, or this improvement is down to an updated app (which I don't think it is, but it's hard to rule it out).

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So, if you've not installed this update yet, I strongly suggest you do. It contains a very serious security path and, as it turns out, some much-needed bug fixes.

Got a problem with iOS 15.3.1? Let me know in the comments below.

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