A Microsoft framework for building cross-platform mobile apps using .NET and C# with native performance and user interfaces.
When deploying an application to background mode on iOS in Xamarin.Forms; I usually deal with this by implementing the ApplicationDidEnterBackground method in my iOS project's AppDelegate.cs file. In this method, I can save the state of the application or perform any necessary cleanup operations before the application goes into the background. When the application is brought back to the foreground I can handle the ApplicationWillEnterForeground method to restore the application state if needed.