From Xamarin in Action by Jim Bennett.
Xamarin in Action teaches you to build cross-platform mobile apps using Xamarin and C#. You’ll explore all the layers of a Xamarin app, from design to deployment. By the end, you’ll be able to build a quality, production-ready Xamarin app on iOS and Android from scratch with a high level of code reuse. This animation shows you can use the MVVM pattern to share most of your code.