Watch how it's made on YouTube:

1. Create custom launch screen in Xcode (File > New > File and choose Launch Screen), see here.
2. Add it to .NET MAUI project Resources folder, see here.
3. Make sure that it has the build action InterfaceDefinition, see here.
4. Include custom launchscreen only for iOS (in csproj), see here.
5. Exclude MauiSplashScreen for iOS (in csproj), see here.
6. Specify launch screen in info.plist, see here.

Note

As of iOS 16.4 your app has to be code signed in order for the splash screen to show up. If you do not sign your app, the splash screen will always show black.