https://devblogs.microsoft.com/xamarin/using-custom-uiviewcontrollers-in-xamarin-forms-on-ios/
Using Custom UIViewControllers in Xamarin.Forms on iOS - Xamarin Blog
Jun 11, 2014 - Xamarin.Forms abstracts the native controls of Android, iOS, and Windows Phone, allowing developers to create native UIs on each platform from a single, shared...
xamarin formsusingcustomiosblog