You made app for Android, iOS, Windows - what about the UI?

Not sure I agree with the prediction:

> My prediction is that Xamarin will come up with its own GUI abstraction framework in future, along the lines of SWT. It is a compromise; but one which delivers a lot of value to developers who want to create cross-platform apps with the maximum amount of shared code.

This will almost certainly create the 'uncanny valley' which the author refers to in an earlier paragraph.

I consider the fact that Xamarin has two APIs for the two platform UIs a real advantage. You can still write your business logic once - so the time to create an iOS and Android app reduces from 2 to 1.x, and you still get the benefit of a fully native feeling app.