I have been involved in commercial Java development the last dozen years or so (although the last three were in a product management role), but I am a total newbie to Xamarin, Mono, Mac, mobile development, Objective C, .NET and C#.
Using Xamarin, I started writing my first mobile app (a chess related game) in November and published it in December:
I now have a beta version of the same app for iOS on TestFlightApp:
and plan to submit it to Apple "soon."
While I am still learning (and there is a lot to learn) the Xamarin tools have made this transition much easier. They have made learning the whole mobile development paradigm easier, have helped tremendously for cross platform functionality and have given me a solid foundation to build on. The knowledge in this forum is awesome and a great help.