Apple took a decision in December that surprised many, and it means that there hundreds of millions of iPhones which need to update as soon as possible. Here are full details of that decision, which iPhones are affected and what you need to do if you have one of them.

Apple iPhone 16 Pro: is yours still on iOS 18?
Getty ImagesWhich iPhones Are Affected By Apple iOS 26?
Before the new software, iOS 26, there was iOS 18. This was on every iPhone from the iPhone XS, iPhone XS Max and iPhone XR onwards. However, these three models cannot upgrade to iOS 26. Every other iPhone, from iPhone 11 onwards, is compatible with the latest cycle. These are the phones that are affected by Apple’s latest upgrade decision.
ForbesiOS 26.3 iPhone Update Release Date: Coming Soon With Benefits For Millions Of PhonesBy David PhelanApple iOS 26 Update Cycles: How It Works
Apple is often a creature of habit: each September, alongside new iPhones, it launched the latest software cycle. That’s now iOS 26, which replaced iOS 18. To ease users into the new system and placate those who want to wait until new software had bedded in before they jump on board, Apple provides alternative updates for a few months. So, alongside iOS 26 came iOS 18.7, followed by iOS 18.7.1 when the first update to the new software came (iOS 26.0.1).
Here’s the thing: after the next releases in early November, which were iOS 26.1 and iOS 18.7.2, many thought that things would repeat themselves when, on Dec. 12, Apple released iOS 18.7.3 and iOS 26.2. But that’s not quite what happened.
Why Hundreds of Millions Must Upgrade To iOS 26 Now
Instead, iOS 18.7.3 was made available for general release only for those three phones which can’t run iOS 26. It meant that from Dec. 12 onwards — over a month ago now — hundreds of millions of iPhones either had to upgrade to iOS 26, no more delaying, or stay on older software. And since iOS 26.2 had a bunch of security updates, that’s not a great idea.
What This Means For Your iPhone
If you have held off upgrading to iOS 26, honestly, don’t wait any longer. Though there have been legitimate reasons for this, such as people with low vision finding the Liquid Glass design of iOS 26 tricky, they are now outweighed, I’d suggest, by the importance of having current protections. Plus, you get a raft of new features that are worth having.
In short, if you’re an iOS 26 resistor, don’t be. Upgrade to the latest software now.
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