Xamarin - Need to integrate API with exisiting Xamarin Cross Platform UI -- 2

I am looking for an experienced Xamarin developer to provide API integration for an existing Xamarin Cross Platform UI. The required API integration is a RESTful integration, supporting both iOS and Android platforms. I also need the developer to incorporate existing APIs which are available in exisiting UI. Experience with Xamarin or related technologies is essential to the completion of this project.