AppTunnel support in Xamarin apps

Apps built with the Xamarin development platform can access network servers various ways. AppTunnel with HTTP/S tunneling is supported only as follows:

The app uses the NSURLConnection or NSURLSession APIs exposed to C# through the Xamarin.iOS binding.
The app uses the ModernHttpClient library with NSURLSession. The ModernHttpClient library with CFNetwork will not work.

For example, the app initializes the instance of the ModernHttpClient as follows:

  var httpClient = new HttpClient (new NativeMessageHandler ());