Sample apps using mapping controls via Xamarin.Android (Google Play services) and Xamarin.iOS (MapKit) as well as Xamarin.Forms. The source code of these projects was largely pulled from Xamarin's online documentation - please reference the links at the bottom of this page for more details.
XamarinMappingDemo - Contains Xamarin.Android and Xamarin.iOS sample map projects XamarinFormsMappingDemo - Contains Xamarin.Forms (with Android and iOS support) sample map projects
Note: To have the Android samples work you will need to register for your own API key.
Please reference the following links for more details on how to setup various map components with Xamarin and Xamarin.Forms: