That's certainly possible for the data part - but a lot harder for UI/code. With the method I'm using, you can actually push code AND UI to the client on the fly. As far as I know, that's a lot more difficult with Xamarin.
Also, the licensing is a lot more flexible than with Xamarin and Qt does provide support for more platforms.
Also, the licensing is a lot more flexible than with Xamarin and Qt does provide support for more platforms.