I am both an IOS and .NET developer. I have been tasked with evaluating Xamarin as a possible option to help us get into the Android space. I am struggling with the advantage Xamarin will give us versus going directly to Android Studio. Our back end in a windows environment and we have our services running either through DataPower or directly through IIS. Either way we publish a REST interface for consumption. Why wouldn't I just build new mobile apps in Android Studio and Xcode and hit my services directly rather than building a whole new layer?