Additional Questions Regarding App Launch Timing

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Created Jun ’25

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I found the following statement on the site TN3187: Migrating to the UIKit scene-based life cycle | Apple Developer Documentation:

"Soon, all UIKit based apps will be required to adopt the scene-based life-cycle, after which your app won’t launch if you don’t. While supporting multiple scenes is encouraged, only adoption of scene life-cycle is required."

In this post, you mentioned that the timing is undecided. https://developer.apple.com/forums/thread/785588

I would like to confirm the following two points additionally.

Could you please confirm whether the timing when the app will not be able to launch is during an iOS update or at another specific time? This will change our response policy.
Does "your app won’t launch" mean that already distributed apps will also not be able to launch? Or does it mean that newly developed apps will fail to build or be rejected during app review?

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Answer 1

darkpaw OP

Jun ’25

I can't speak to timing, but what will happen has to happen in an iOS update.

There will be a future version of iOS where an application that does not support the scene-based lifecycle will not launch.

So, let's look at the options:

You have an existing app on the App Store. You released it ages ago. It uses the app lifecycle. You have not updated it to use the scene-based lifecycle. This app will launch on older versions of iOS, but it will not launch on the new version of iOS. (This will trim a lot of old apps from the App Store.)
You have an existing app on the App Store. You released it ages ago. It uses the app lifecycle. You update it to use the scene-based lifecycle. This app launches on the old versions of iOS, and the new version of iOS.
You're developing an app in Xcode that supports an older version of iOS that allows the app lifecycle method, and your app uses that app lifecycle method. You can build this app and run it on that version of iOS without issue. It launches fine. If you attempt to run it on the latest version of iOS, it will not launch.
You're developing an app in Xcode that supports an older version of iOS that allows the old lifecycle method, but your app uses the new scene-based lifecycle method. You can build this app and run it on the old version of iOS without issue. It launches fine. If you run it on the latest version of iOS, it launches fine.

Now, all new builds submitted to the App Store are supposed to support the latest version of iOS, so when Apple release this new version of iOS that requires the scene-based lifecycle method, and you attempt to upload an app that does not use the scene-based lifecycle method then your app will likely be rejected by the upload or validation process.

As an aside, I recently updated four of my apps to use the scene-based lifecycle, and it was painless. If you need help in migrating, just start a new app in Xcode and it will have the scene-based lifecycle in it. You can see how it's structured and just copy the bits into your existing app. Sure, you might need to rework some things, but it's nowhere near as big a deal as you might think.

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Answer 2

Frameworks Engineer OP

Apple

Jun ’25

Recommended

We clarify these questions in our UIKit WWDC talks this year:

Could you please confirm whether the timing when the app will not be able to launch is during an iOS update or at another specific time? This will change our response policy.

Check out these timestamps:

https://developer.apple.com/videos/play/wwdc2025/243/?time=1317

https://developer.apple.com/videos/play/wwdc2025/282/?time=136

When building with the SDK from the next major release after iOS 26, iPadOS 26, macOS 26 and visionOS 26, UIKit will assert that all apps have adopted UIScene life cycle. Apps that fail this assert with crash on launch.

So not only does this require the next major release to happen, it requires you to build with the SDK, which is not typically a requirement right away.

Still, this should be prioritized.

Does "your app won’t launch" mean that already distributed apps will also not be able to launch? Or does it mean that newly developed apps will fail to build or be rejected during app review?

UIKit will assert and the app will crash when you build with the next major release's SDK. If you do this, you will see it at your desk if you submit it. There's not behavior difference between distributed or new apps.

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