public override bool OpenUrl(UIApplication application, NSUrl url, string sourceApplication, NSObject annotation)
        {
            // Handle App Invite requests
            var invite = Invite.HandleUrl(url, sourceApplication, annotation);

            if (invite != null)
            {
                var message = string.Format("Deep link from {0} \nInvite ID: {1}\nApp URL: {2}",
                                            sourceApplication, invite.InviteId, invite.DeepLink);
                new UIAlertView(@"Deep-link Data", message, null, "OK").Show();

                return(true);
            }

            return(SignIn.SharedInstance.HandleUrl(url, sourceApplication, annotation));
        }