Due to its specifications our SL/WPF controls are not compatible with Xamarin. However, you could use our backend services with Xamarin as described in the following blog post:
http://developer.telerik.com/products/using-xamarin-with-telerik-backend-services-and-analytics/
    
Additionally, I would suggest that you take a look at our AppBuilder ( http://www.telerik.com/appbuilder ) - our Integrated Cloud Environment (ICE) for developing hybrid apps for mobile devices.