Updated FirstRunPage

FirstRunPage.xaml.cs

    public sealed partial class FirstRunPage : VisualStateAwarePage
    {
        public FirstRunPage()
        {
            this.InitializeComponent();
        }

        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
            //base.OnNavigatedTo(e);
#if WINDOWS_PHONE_APP
            HardwareButtons.BackPressed += HardwareBack_OnPressed;            
#endif
        }

        protected override void OnNavigatedFrom(NavigationEventArgs e)
        {
            //base.OnNavigatedFrom(e);
#if WINDOWS_PHONE_APP
            HardwareButtons.BackPressed -= HardwareBack_OnPressed;
#endif
        }

        protected override void GoBack(object sender, RoutedEventArgs eventArgs)
        {
            return;
        }

        private void HardwareBack_OnPressed(object sender, BackPressedEventArgs e)
        {
            //Action handledCallback = () => e.Handled = true;
            //var state = new Dictionary<string, object> { { "Callback", handledCallback } };
            e.Handled = true;
            
            // ((INavigationAware)this.DataContext).OnNavigatedTo("Back", NavigationMode.Back, state);
        }        
    }