Xamarin iOS apps are the same as iOS specific development using Swift or Objective-C. But it uses (mostly) the same code as Android, making it quicker to build to high standards across both platforms.
Building an Android app in Xamarin gives you all the possibilities of native development using Java or C#.
Xamarin is a great framework for developing cross platform apps with benefits all round - for the client who wants their app on multiple platforms without the cost of multiple apps, and the developer who only has to develop and maintain a single code base instead of managing multiple.
Senior developer, Eastpoint Software