It is model for the Info App-Template.
        /// <summary>
        /// The methods provided in this section are simply used to allow
        /// NavigationHelper to respond to the page's navigation methods.
        /// <para>
        /// Page specific logic should be placed in event handlers for the
        /// <see cref="NavigationHelper.LoadState"/>
        /// and <see cref="NavigationHelper.SaveState"/>.
        /// The navigation parameter is available in the LoadState method
        /// in addition to page state preserved during an earlier session.
        /// </para>
        /// </summary>
        /// <param name="e">Provides data for navigation methods and event
        /// handlers that cannot cancel the navigation request.</param>
        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
            if (AppList.getMyAppList().myappList.Count > 0)
                btnMyApps.Visibility = Visibility.Visible;
            else btnMyApps.Visibility = Visibility.Collapsed;
            app = AppInstance.app;
            var localSettings = Windows.Storage.ApplicationData.Current.LocalSettings;
            if (localSettings.Values.ContainsKey(app.Name))
            appInstalled=(bool)(localSettings.Values[app.Name]);
            if (appInstalled) btnAppInstall.Content = "LAUNCH";
            else btnAppInstall.Content = "INSTALL";

            webAppReviews.NavigateToString(getHtmlComment());
           

            txtAppName.Text = app.Name;
            txtAppAuthor.Text = app.Author;
            if (app.Description.Length > 50)
            {
                txtShowMore = false;
                txtAppDetails.Text = app.Description.Substring(0, 50) + "...";
                detailsShowMore.Content = "more";
            }
            else
            { txtAppDetails.Text = app.Description;
            detailsShowMore.Visibility = Visibility.Collapsed;
            }
            txtAddInfo1.Text=("Author: \nAuthor Email: \nCategory: \nType: ");
            txtAddInfo2.Text=(app.Author + "\n" + app.AuthorEmail + "\n" + app.Category + "\n" + app.Type);
            
            List<Image> images = new List<Image>();
            foreach(string screenshot in app.Screenshots)
            {
                Image image = new Image();
                image.Source = new BitmapImage(new Uri(screenshot));
                images.Add(image);
            }
            FullScreenshots.ItemsSource = images;
            imgAppIcon.Source = new BitmapImage(new Uri(app.AppIcon));
            GridScreenshots.ItemsSource = app.Screenshots;
            this.navigationHelper.OnNavigatedTo(e);
        }
 /// <summary>
 /// Executed when the app is long tapped. Context menu appears now.
 /// </summary>
 /// <param name="sender">Object Sender is a parameter called Sender that contains a reference to the control/object that raised the event.</param>
 /// <param name="e">RoutedEventArgs e is a parameter called e that contains the event data, see the RoutedEventArgs MSDN page for more information.</param>
 private void StackPanel_Holding(object sender, HoldingRoutedEventArgs e)
 {
     FrameworkElement senderElement = sender as FrameworkElement;
     StackPanel stackPanel = sender as StackPanel;
     TextBlock txt = (TextBlock)stackPanel.Children.ElementAt(1);
     foreach (Apps app in AppList.getAppList().appList)
     {
         if (app.Name.Equals(txt.Text))
         {
             appHolding = app; break;
         }
     }
     var localSettings = Windows.Storage.ApplicationData.Current.LocalSettings;
     FlyoutBase flyoutBase = FlyoutBase.GetAttachedFlyout(senderElement);
     flyoutBase.ShowAt(senderElement);
 }