Upgrading to a new version of iOS on your iPhone or iPad is an exciting experience, with new features and a tweaked interface to look forward to. But there are sometimes downsides too - such as favourite apps not working any more.

In this article we look at iOS 12, and help you to identify which of your apps will stop working if you make the upgrade.

Big and new apps

Let's split the entire ecosystem of iOS apps into two groups, and start with apps that are high-profile and/or relatively 'current' - ie apps that still make money, have high active user numbers, and are updated reasonably regularly.

For apps like this you should be fine when updating to iOS 12. If there are any issues running on the new platform, the app's developers will almost certainly release a fix as a free update - that's assuming they haven't done so already, since iOS 12 has been in the public sphere since September 2018 and developers have had the beta since June.

(You can check for updates in the App Store app on your iPhone or iPad, under the tab labelled Updates.)

If you're not sure if a beloved app is compatible with iOS 12 or if it's going to receive an update to become so, contact the developer and ask.

Small and old apps

If you like an app that's a bit older, and maybe quite niche - or, most importantly, it hasn't been updated in a while - then you might be in trouble. Plenty of such apps do not work with iOS 12, but it's impossible for us to list them individually, because there are hundreds of thousands of them.

So our advice would be to assume that any old, rarely updated app is in peril every time you update iOS. If it's a dealbreaker for you, contact the developer before making the update and ask if it will still work.

The 32-bit purge

As part of the iOS 11 update in autumn 2017, Apple announced that 32-bit apps would no longer work, as the whole App Store moved to 64-bit instead.

For a lot of apps (including almost all recent, popular and high-profile apps) this wasn't an issue, as they had updated before the switch; and many others have updated to 64-bit in the year since the change was made. But some smaller and/or older ones did not have the resources to update, or chose not, and these will not work in either iOS 11 or iOS 12.

That means you may find some of your apps no longer work in iOS or have disappeared.

Note that this was an issue which appeared between iOS 10 and iOS 11. If you're upgrading from 10 or earlier, this is something you need to think about, but those moving from iOS 11 to 12 do not. Any apps that worked in iOS 11 are 64-bit and won't be affected by the purge.

Why the switch to 64-bit?

When the iPhone 5s came out back in 2013 it was the first of Apple's phones to support the new 64-bit architecture of iOS 7. Since then all iPhones and iPads have followed suit, thanks to the A7 chip and its successors.

In 2015 Apple also made it a requirement that new apps or updates in the App Store needed to come with 64-bit support. This meant that many leading apps were ready for this latest transition years in advance.

When iOS 11 launched, the makeover was complete. All Apple devices and apps were then able to take advantage of the optimised 64-bit apps, which can run more efficiently and make full use of the operating system.

Essentially it meant the drag factor on resources that previously existed to support 32-bit apps was removed. Chocks away, Biffy!

Which apps won't work on iOS 12?

How can I find 32-bit apps on my device?

Discovering any old apps that haven't been updated is very simple.

On your iPhone or iPad go to Settings > General > About, and then look for Applications in the list.

Which apps won't work on iOS 12: Settings

If you don't have any applications that are 32-bit then tapping Applications will do nothing. But if you see an arrow on the right side of that section then tap on it and you'll be presented with a list of all the 32-bit apps on your device.

Which apps won't work in iOS 12: 32-bit apps

What if my favourite apps appear on the list?

Sadly, there's not a lot you can do to get these apps working again, as many of them will have long since been abandoned by their creators.

If you tap on the app in the 32-bit list you'll be taken to its page on the App Store. Be sure to check in the description whether the developer has released a newer version of the app under a different name or as a sequel to the original.

You will have to purchase this separately, as it's essentially a new app, but if you can't live without it then at least you can move to the latest iteration. Otherwise you'll need to search for alternatives.

For some ideas try perusing our various guides to iOS apps. These include the Best free iPhone apps, Best iPhone & iPad games, Best kids apps, Best messaging apps, and Best meditation and mindfulness apps.

Hopefully among these lists you'll find ones to replace your old favourites, or maybe even stumble over a future classic. Happy hunting.