Auto-Implemented Back Button Windows 10

App.xaml.cs

// Stole this from http://devcenter.wintellect.com/jprosise/handling-the-back-button-in-windows-10-uwp-apps

sealed partial class App : Application
{
    public App()
    {
        this.InitializeComponent();
        this.Suspending += OnSuspending;
    }

    protected override void OnLaunched(LaunchActivatedEventArgs e)
    {
        Frame rootFrame = Window.Current.Content as Frame;

        // Do not repeat app initialization when the Window already has content,
        // just ensure that the window is active
        if (rootFrame == null)
        {
            // Create a Frame to act as the navigation context and navigate to the first page
            rootFrame = new Frame();

            rootFrame.NavigationFailed += OnNavigationFailed;
            rootFrame.Navigated += OnNavigated;

            if (e.PreviousExecutionState == ApplicationExecutionState.Terminated)
            {
                // TODO: Load state from previously suspended application
            }

            // Place the frame in the current Window
            Window.Current.Content = rootFrame;

            // Register a handler for BackRequested events and set the
            // visibility of the Back button
            SystemNavigationManager.GetForCurrentView().BackRequested += OnBackRequested;

            SystemNavigationManager.GetForCurrentView().AppViewBackButtonVisibility =
                rootFrame.CanGoBack  ?
                AppViewBackButtonVisibility.Visible :
                AppViewBackButtonVisibility.Collapsed;
        }

        if (rootFrame.Content == null)
        {
            // When the navigation stack isn't restored navigate to the first page,
            // configuring the new page by passing required information as a navigation
            // parameter
            rootFrame.Navigate(typeof(MainPage), e.Arguments);
        }

        // Ensure the current window is active
        Window.Current.Activate();
    }

    void OnNavigationFailed(object sender, NavigationFailedEventArgs e)
    {
        throw new Exception("Failed to load Page " + e.SourcePageType.FullName);
    }

    private void OnNavigated(object sender, NavigationEventArgs e)
    {
        // Each time a navigation event occurs, update the Back button's visibility
        SystemNavigationManager.GetForCurrentView().AppViewBackButtonVisibility =
            ((Frame)sender).CanGoBack ?
            AppViewBackButtonVisibility.Visible :
            AppViewBackButtonVisibility.Collapsed;
    }

    private void OnSuspending(object sender, SuspendingEventArgs e)
    {
        var deferral = e.SuspendingOperation.GetDeferral();
        // TODO: Save application state and stop any background activity
        deferral.Complete();
    }

    private void OnBackRequested(object sender, BackRequestedEventArgs e)
    {
        Frame rootFrame = Window.Current.Content as Frame;

        if (rootFrame.CanGoBack)
        {
            e.Handled = true;
            rootFrame.GoBack();
        }
    }
}