You have two options: 1. You can bind the native iOS or Android library into C#, which is relatively straightforward: http://developer.xamarin.com/guides/ios/

You have two options: 1. You can bind the native iOS or Android library into C#, which is relatively straightforward: http://developer.xamarin.com/guides/ios/advanced_topics/binding_objective-c/ http://developer.xamarin.com/guides/ios/advanced_topics/bind... http://developer.xamarin.com/guides/android/advanced_topics/java_integration_overview/binding_a_java_library_ http://developer.xamarin.com/guides/android/advanced_topics/...(.jar)/ 2. Or you could create a single, managed library in C#, which would also make it easier to get Windows support. Option 2 is more work.