iOS does not provide a public API for an app to terminate itself and automatically launch a fresh process of the same app. Android-style full process restart is not available on iOS with public APIs. restart_app supports two iOS behaviors:
  1. Flutter engine restart, recommended.
  2. Notification fallback, legacy and explicit only.

​
Configure the host app

The host app owns GeneratedPluginRegistrant, so iOS engine restart requires one app-side setup step. Choose the setup that matches your iOS lifecycle.

​
Flutter 3.41+ UIScene apps

Use this setup when your app has migrated to Flutter’s UIScene lifecycle and your delegate already looks like @objc class AppDelegate: FlutterAppDelegate, FlutterImplicitEngineDelegate. Keep the normal plugin registration for the implicit app engine in didInitializeImplicitFlutterEngine. Add RestartAppPlugin.configureEngineRestart in application(_:didFinishLaunchingWithOptions:) so restart_app can register plugins on each newly created engine: 
import UIKit
import Flutter
import restart_app

@main
@objc class AppDelegate: FlutterAppDelegate, FlutterImplicitEngineDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    RestartAppPlugin.configureEngineRestart { engine in
      GeneratedPluginRegistrant.register(with: engine)
    }

    return super.application(
      application,
      didFinishLaunchingWithOptions: launchOptions
    )
  }

  func didInitializeImplicitFlutterEngine(
    _ engineBridge: FlutterImplicitEngineBridge
  ) {
    GeneratedPluginRegistrant.register(with: engineBridge.pluginRegistry)
  }
}
This follows Flutter’s UIScene migration model: the initial engine is registered through didInitializeImplicitFlutterEngine, and restarted engines are registered through the restart_app callback above. restart_app automatically looks for the active foreground UIWindowScene and replaces that scene’s key window root FlutterViewController. If your app has multiple scenes or a custom native shell, pass a windowProvider or viewControllerInstaller to configureEngineRestart so the plugin targets the correct window. If you implement your own SceneDelegate, keep Flutter’s scene lifecycle wiring there too: subclass FlutterSceneDelegate or conform to FlutterSceneLifeCycleProvider, as described in Flutter’s UISceneDelegate migration guide.

​
Classic AppDelegate apps

Use this setup only when your app still registers plugins from application(_:didFinishLaunchingWithOptions:). In ios/Runner/AppDelegate.swift: 
import UIKit
import Flutter
import restart_app

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    RestartAppPlugin.configureEngineRestart { engine in
      GeneratedPluginRegistrant.register(with: engine)
    }

    GeneratedPluginRegistrant.register(with: self)

    return super.application(
      application,
      didFinishLaunchingWithOptions: launchOptions
    )
  }
}
Then call: 
final result = await Restart.restartApp();
RestartMode.platformDefault uses Flutter engine restart on iOS when this setup is present. If this setup is missing, platformDefault fails cleanly on iOS instead of falling back to notification plus exit(0). To request the engine path explicitly: 
final result = await Restart.restartApp(
  mode: RestartMode.flutterEngine,
);

​
What gets reset

Engine restart resets:
  • Dart root isolate
  • Flutter widget tree
  • Flutter engine-owned platform channels
  • Flutter plugin registrations for the new engine
  • Platform-view factory registrations for the new engine
It does not reset:
  • The iOS process
  • Swift, Objective-C, C, or C++ static/global state
  • Native singleton state
  • Native resources retained by plugins
  • Unrelated Flutter engines or background isolates
  • Native app launch lifecycle callbacks from a real process launch
For code-push systems and plugins with heavy native state, verify behavior in a real release build. Same-process engine restart is not equivalent to full process restart.

​
Notification fallback

Use the notification fallback only when the tradeoff is acceptable: 
Restart.restartApp(
  mode: RestartMode.notificationFallback,
  notificationTitle: 'Update applied',
  notificationBody: 'Tap to reopen the app.',
);
The plugin requests notification permission at the moment of restart. If not already granted, iOS shows the system prompt right before exit, which feels abrupt. Request permission earlier in your app lifecycle. The permission_handler package works well for this. If notification permission has been denied, restartApp() returns a failed result.

​
Provisioning profiles

restart_app uses local notifications only, not push notifications. It adds no push-related entitlements to your app. If you see "requires a provisioning profile with the Push Notifications feature" when exporting an IPA, another dependency is the cause, commonly firebase_messaging. Add the Push Notifications capability to your distribution provisioning profile.