[keithwarren]

YMMV but for me, there was not 'learning' of Xamarin. There really is no Xamarin framework - there is the mobile frameworks themselves for which there is an almost 1:1 translation. CalculateFoo in ObjC or Java will in nearly every case be CalculateFoo in C#. In the cases where the recommended method is to use a higher level abstraction (like for table data in iOS), the option to use a mirror of the ObjC pattern is there but there is an easier approach available if you choose that.

The key for me was understanding the idiosyncrasies of both Android and iOS and their patterns and then using C# to craft as much reusable code as possible. It drives my approach and I failed to get the re-use level I wanted on my first true cross platform app build, but since I have learned those lessons I have gotten much better at it.

(note: I have yet to use Xamarin.Forms, this experience is based on Xamarin in the past 15 months)