The UIScene life cycle is required in iOS 27

Apple says to migrate if either is true: the UIApplicationSceneManifest key is missing from your information property list or has no configurations, or your app delegate doesn’t implement application(_:configurationForConnecting:options:). UIKit has logged a warning about this since iOS 18.4 and a stronger one in iOS 26, so check your console. The requirement applies to apps built with the iOS 27 SDK, which Apple says App Store uploads must use starting April 2027; see Xcode 27 release and requirements. One developer report on Stack Overflow shows the failure as a launch-time runtime issue mentioning _UIApplicationEvaluateRuntimeIssueForNoSceneLifecycleAdoption.

In Xcode, select your app target, open General, and choose Scene manifest under Deployment Info, which adds a UIApplicationSceneManifest entry. If your root view controller comes from a storyboard, put the storyboard name in the scene configuration and UIKit sets up the window. If you build UI in code, create a SceneDelegate that conforms to UIWindowSceneDelegate and create the UIWindow in scene(_:willConnectTo:options:). Then move UI life-cycle code from the app delegate to the scene delegate as in the table; the app delegate keeps process-level events. Apps that need different scenes based on user activity implement application(_:configurationForConnecting:options:) instead. CarPlay apps use CPTemplateApplicationScene. Test in Split View, Slide Over and Stage Manager on iPad afterwards.

Flutter’s docs say Flutter apps built with Xcode 27 that don’t adopt UIScene fail on startup. Since Flutter 3.41, UIScene is the default and an unmodified AppDelegate is migrated automatically when you run flutter run or flutter build ios; the CLI prints «Finished migration to UIScene lifecycle». With a custom AppDelegate or an older Flutter, migrate by hand: conform the app delegate to FlutterImplicitEngineDelegate and move plugin registration into didInitializeImplicitFlutterEngine. Plugins that use application life-cycle events and add-to-app setups have their own steps.

In Expo SDK 58, npx expo prebuild generates SceneDelegate.swift and the scene manifest, and Expo forwards URL, user activity, Handoff and quick action events so config plugins keep working. If you manage the ios folder by hand or have a bare React Native app, apply Apple’s steps above to the native project, or follow Expo’s migration guide for app delegate overrides.

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