I ran our upcoming CSLA.Android Dlls through the tool at scan.xamarin.com and came up with a 97% compatibility. At first is seemed strange as these were Xamarin Android created DLLs; then I realized what had happened. In the Android version of the framework we re-implement a missing portion of the .Net Framework, System.ComponentModel.DataAnnotations. The scan tool must look for references to non implemented parts of the framework and not check to see if some other re-implemented version exists (even if it is right there in the DLL it is checking).
I don't think this is a big deal, I just found it rather humorous that our Xamarin Android DLL wasn't coming back as 100% compatible with Android. Interestingly enough, it did say it was more compatible with iOS (99%).