async void SendRegistrationToAppServer(int userId, string email, string token)
        {
            var access_key     = "AKIAJLTJVDVD3ECKFSBQ";
            var secret_key     = "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";
            var applicationArn = "arn:aws:sns:us-west-2:490523474570:app/GCM/idd_android";

            var snsClient = new AmazonSimpleNotificationServiceClient(access_key, secret_key, RegionEndpoint.USWest2);

            Console.WriteLine(snsClient.ToString());

            var response = await snsClient.CreatePlatformEndpointAsync(new CreatePlatformEndpointRequest
            {
                CustomUserData         = email,
                Token                  = token,
                PlatformApplicationArn = applicationArn
            });



            var responseApi = await IDD.UserService.PostRegisterSNSDevice(userId, response.EndpointArn, applicationArn);

            if (responseApi != null)
            {
                if (responseApi["codigo"].ToString() == "1")
                {
                    var s = responseApi["data"].ToString();
                    Console.WriteLine("se guardo correctmente el token" + userId.ToString() + "_" + response.EndpointArn);

                    ISharedPreferences       prefs  = Application.Context.GetSharedPreferences("PREF_NAME", FileCreationMode.Private);
                    ISharedPreferencesEditor editor = prefs.Edit();
                    editor.PutString("endpoint_arn", response.EndpointArn);
                    editor.Apply();
                }
            }

            Console.WriteLine("endpoint arn___" + response.EndpointArn + "___");
        }