No,Category,Guideline,Description,Do,Don't,Code Good,Code Bad,Severity,Docs URL,Applies To,Status,Verified At
1,XAML,Use x:Bind for compiled bindings,Compile-time validated bindings with better performance,x:Bind for type-safe performant bindings,{Binding} when x:Bind is available,"<TextBlock Text=""{x:Bind ViewModel.Name, Mode=OneWay}""/>","<TextBlock Text=""{Binding Name}""/>",High,https://learn.microsoft.com/en-us/windows/uwp/xaml-platform/x-bind-markup-extension,uwp legacy,deprecated,2026-08-13
2,XAML,Use x:Load for deferred elements,Delay creation of elements until needed,x:Load=False for hidden or conditional panels,Loading all UI elements at page load,"<StackPanel x:Name=""AdvancedPanel"" x:Load=""{x:Bind ShowAdvanced, Mode=OneWay}"">",Collapsed StackPanel that is always instantiated,Medium,https://learn.microsoft.com/en-us/windows/uwp/xaml-platform/x-load-attribute,uwp legacy,deprecated,2026-08-13
3,XAML,Use x:Phase for incremental item rendering,Render list items in priority phases,x:Phase on secondary content in item DataTemplates,All template content loaded in one pass,"<TextBlock x:Phase=""1"" Text=""{x:Bind Description}""/>",Complex DataTemplate with no phasing,Medium,https://learn.microsoft.com/en-us/windows/uwp/xaml-platform/x-phase-attribute,uwp legacy,deprecated,2026-08-13
4,XAML,Use x:DefaultBindMode,Reduce repetitive Mode= declarations,x:DefaultBindMode=OneWay on containers,Mode=OneWay on every individual x:Bind,"<StackPanel x:DefaultBindMode=""OneWay"">",Mode=OneWay repeated on every binding in a panel,Low,https://learn.microsoft.com/en-us/windows/uwp/xaml-platform/x-bind-markup-extension,uwp legacy,deprecated,2026-08-13
5,XAML,Use x:DeferLoadStrategy for legacy support,Deferred loading before x:Load was available,x:Load (preferred) or x:DeferLoadStrategy=Lazy,Eagerly loading rarely shown UI,"x:Load=""False"" (or x:DeferLoadStrategy=""Lazy"" on older targets)",Always-loaded panels toggled with Visibility,Low,https://learn.microsoft.com/en-us/windows/uwp/xaml-platform/x-deferloadstrategy-attribute,uwp legacy,deprecated,2026-08-13
6,Controls,Use NavigationView for app shell,Standard UWP navigation pattern with hamburger menu,NavigationView for top-level navigation,Custom SplitView hamburger menu,"<NavigationView><NavigationView.MenuItems><NavigationViewItem Content=""Home"" Icon=""Home""/></NavigationView.MenuItems></NavigationView>",Custom SplitView with manual toggle button,High,https://learn.microsoft.com/en-us/windows/uwp/design/controls-and-patterns/navigationview,uwp legacy,deprecated,2026-08-13
7,Controls,Use CommandBar for app actions,Standard app bar for primary commands,CommandBar with AppBarButtons,Custom StackPanel toolbar,"<CommandBar><AppBarButton Icon=""Save"" Label=""Save""/></CommandBar>","<StackPanel Orientation=""Horizontal""><Button>Save</Button></StackPanel>",Medium,https://learn.microsoft.com/en-us/windows/apps/develop/ui/controls/command-bar,uwp legacy,deprecated,2026-08-13
8,Controls,Use ContentDialog for modals,System-styled modal dialogs,ContentDialog for confirmations and input,Custom popup overlays,"<ContentDialog Title=""Confirm"" PrimaryButtonText=""Yes"" CloseButtonText=""No""/>",Grid overlay with manual focus trapping,Medium,https://learn.microsoft.com/en-us/windows/uwp/design/controls-and-patterns/dialogs-and-flyouts/dialogs,uwp legacy,deprecated,2026-08-13
9,Controls,Use AutoSuggestBox for search,Built-in search box with suggestions,AutoSuggestBox with QuerySubmitted and SuggestionChosen,TextBox with manual suggestion popup,"<AutoSuggestBox QueryIcon=""Find"" TextChanged=""OnTextChanged"" SuggestionChosen=""OnChosen"" QuerySubmitted=""OnQuerySubmitted""/>",TextBox with custom Popup and ListBox for suggestions,Medium,https://learn.microsoft.com/en-us/windows/uwp/design/controls-and-patterns/auto-suggest-box,uwp legacy,deprecated,2026-08-13
10,Controls,Use CalendarDatePicker and TimePicker,Platform-consistent date and time selection,Built-in date and time pickers,Custom date selection controls,"<CalendarDatePicker Header=""Start date""/><TimePicker Header=""Time""/>",TextBox with date parsing and validation,Low,https://learn.microsoft.com/en-us/windows/uwp/design/controls-and-patterns/date-and-time,uwp legacy,deprecated,2026-08-13
11,Controls,Use PersonPicture for user avatars,Consistent avatar display with fallback initials,PersonPicture with DisplayName and ProfilePicture,Custom Ellipse with ImageBrush for avatars,"<PersonPicture DisplayName=""Jane Doe"" ProfilePicture=""{x:Bind AvatarUri}""/>","<Ellipse><Ellipse.Fill><ImageBrush ImageSource=""avatar.png""/></Ellipse.Fill></Ellipse>",Low,https://learn.microsoft.com/en-us/windows/uwp/design/controls-and-patterns/person-picture,uwp legacy,deprecated,2026-08-13
12,Styling,Use ThemeResource for adaptive colors,Colors that switch with light and dark theme,ThemeResource for all color references,Hardcoded hex values that break in dark mode,"Foreground=""{ThemeResource SystemControlForegroundBaseHighBrush}""","Foreground=""#000000""",High,https://learn.microsoft.com/en-us/windows/uwp/design/style/color,uwp legacy,deprecated,2026-08-13
13,Styling,Use Fluent Design materials,Acrylic translucent material for depth,Built-in Fluent materials for depth and motion,Custom shader effects for blur and reveal,"<Grid Background=""{ThemeResource SystemControlAcrylicWindowBrush}""/>",Custom CompositionEffectBrush recreating acrylic,Medium,https://learn.microsoft.com/en-us/windows/uwp/design/style/acrylic,uwp legacy,deprecated,2026-08-13
14,Styling,Use Lightweight Styling,Override control resource keys for subtle changes,Lightweight styling resource overrides,Full ControlTemplate copy for small tweaks,"<Button><Button.Resources><SolidColorBrush x:Key=""ButtonBackground"" Color=""Blue""/></Button.Resources></Button>",Entire ControlTemplate copied to change background,Medium,https://learn.microsoft.com/en-us/windows/uwp/design/controls-and-patterns/xaml-styles#lightweight-styling,uwp legacy,deprecated,2026-08-13
15,Styling,Use implicit styles for consistency,TargetType without x:Key applies to all instances,Implicit Style for default control appearance,Repeating Setters on every control instance,"<Style TargetType=""Button""><Setter Property=""CornerRadius"" Value=""4""/></Style>","CornerRadius=""4"" on every Button in the page",Medium,https://learn.microsoft.com/en-us/windows/uwp/design/controls-and-patterns/xaml-styles,uwp legacy,deprecated,2026-08-13
16,Styling,Use VisualStateManager for visual states,Define visual states with Setters that change properties when triggered,VisualStateGroup containing VisualStates with Setter targets,Toggling Visibility from code-behind on SizeChanged,"<VisualStateGroup><VisualState x:Name=""Wide""><VisualState.Setters><Setter Target=""root.Orientation"" Value=""Horizontal""/></VisualState.Setters></VisualState></VisualStateGroup>",SizeChanged handler that flips Orientation in code-behind,High,https://learn.microsoft.com/en-us/windows/uwp/design/layout/layouts-with-xaml,uwp legacy,deprecated,2026-08-13
17,Navigation,Use Frame for page navigation,Windows.UI.Xaml.Controls.Frame for UWP page navigation,Frame.Navigate with typed parameters,Swapping UserControls manually,"rootFrame.Navigate(typeof(DetailPage), itemId);",contentArea.Content = new DetailPage();,Medium,https://learn.microsoft.com/en-us/windows/uwp/design/basics/navigate-between-two-pages,uwp legacy,deprecated,2026-08-13
18,Navigation,Handle back button correctly,Provide an in-app Back button styled with NavigationBackButtonNormalStyle and handle SystemNavigationManager.BackRequested for hardware back gamepad B and Tablet-Mode back; also handle CoreDispatcher.AcceleratorKeyActivated for Alt+Left,In-app NavigationBackButtonNormalStyle button plus SystemNavigationManager.BackRequested handler,Relying on the deprecated title-bar back button (AppViewBackButtonVisibility) or ignoring system back signals,SystemNavigationManager.GetForCurrentView().BackRequested += OnBackRequested;,No back button support on phone or tablet,High,https://learn.microsoft.com/en-us/windows/uwp/ui-input/back-navigation,uwp legacy,deprecated,2026-08-13
19,Navigation,Support deep linking with protocol activation,Respond to URI activation and toast taps,OnActivated handler with proper page routing,Ignoring activation arguments,protected override void OnActivated(IActivatedEventArgs args) { if (args.Kind == ActivationKind.Protocol) { ... } },Empty OnActivated ignoring URI parameters,Medium,https://learn.microsoft.com/en-us/windows/uwp/launch-resume/handle-uri-activation,uwp legacy,deprecated,2026-08-13
20,Navigation,Use ConnectedAnimations for continuity,Smooth transitions between pages,ConnectedAnimationService for shared element transitions,Abrupt page transitions with no visual continuity,"ConnectedAnimationService.GetForCurrentView().PrepareToAnimate(""image"", sourceImage);",No transition animation between list and detail,Low,https://learn.microsoft.com/en-us/windows/uwp/design/motion/connected-animation,uwp legacy,deprecated,2026-08-13
21,Data Binding,Implement INotifyPropertyChanged,Enable UI updates on property changes,INotifyPropertyChanged on all ViewModels,Auto-properties without notification,public string Title { get => _title; set { _title = value; OnPropertyChanged(); } },public string Title { get; set; } expecting UI updates,High,https://learn.microsoft.com/en-us/windows/uwp/data-binding/data-binding-in-depth,uwp legacy,deprecated,2026-08-13
22,Data Binding,Use ObservableCollection for lists,Collection change notifications for ItemsSources,ObservableCollection<T> for bound lists,List<T> for data-bound collections,ObservableCollection<Item> Items { get; } = new();,List<Item> Items { get; set; } = new();,High,https://learn.microsoft.com/en-us/windows/uwp/data-binding/data-binding-in-depth,uwp legacy,deprecated,2026-08-13
23,Data Binding,Use function bindings with x:Bind,Call static methods directly in markup,x:Bind to static converter methods,IValueConverter for trivial transforms,"<TextBlock Visibility=""{x:Bind local:Converters.BoolToVisibility(IsActive), Mode=OneWay}""/>",Full IValueConverter class for bool to Visibility,Medium,https://learn.microsoft.com/en-us/windows/uwp/data-binding/function-bindings,uwp legacy,deprecated,2026-08-13
24,Data Binding,Specify Mode on x:Bind,x:Bind defaults to OneTime not OneWay,Mode=OneWay or TwoWay when live updates needed,Omitting Mode and getting stale UI,"Text=""{x:Bind Title, Mode=OneWay}""","Text=""{x:Bind Title}"" expecting live updates",High,https://learn.microsoft.com/en-us/windows/uwp/xaml-platform/x-bind-markup-extension,uwp legacy,deprecated,2026-08-13
25,Data Binding,Use CollectionViewSource for grouping,Group and sort collections declaratively,CollectionViewSource for grouped ListView and GridView,Manual grouping logic in code-behind,"<CollectionViewSource x:Key=""GroupedItems"" IsSourceGrouped=""True"" Source=""{x:Bind GroupedData}""/>",Manual loop building grouped StackPanels,Medium,https://learn.microsoft.com/en-us/windows/uwp/data-binding/data-binding-in-depth,uwp legacy,deprecated,2026-08-13
26,Performance,Use ListView and GridView virtualization,Only creates containers for visible items,Default virtualization in ListView and GridView,Setting ItemsPanel to non-virtualizing panel,"<ListView ItemsSource=""{x:Bind Items}""/> (virtualizes by default)",<ListView><ListView.ItemsPanel><ItemsPanelTemplate><StackPanel/></ItemsPanelTemplate></ListView.ItemsPanel></ListView>,High,https://learn.microsoft.com/en-us/windows/uwp/debug-test-perf/optimize-gridview-and-listview,uwp legacy,deprecated,2026-08-13
27,Performance,Use ISupportIncrementalLoading,Load data on demand as user scrolls,ISupportIncrementalLoading for large datasets,Loading entire collection upfront,"class IncrementalSource : ObservableCollection<Item>, ISupportIncrementalLoading",await LoadAll() loading 50K items at startup,Medium,https://learn.microsoft.com/en-us/windows/uwp/data-binding/data-binding-in-depth,uwp legacy,deprecated,2026-08-13
28,Performance,Reduce XAML visual tree depth,Simpler trees layout and render faster,Flat templates with minimal nesting,Deeply nested panels in DataTemplates,<StackPanel><TextBlock/><TextBlock/></StackPanel> in item template,<Grid><Border><StackPanel><Grid>... 8 levels in item template,Medium,https://learn.microsoft.com/en-us/windows/uwp/debug-test-perf/optimize-xaml-loading,uwp legacy,deprecated,2026-08-13
29,Performance,Use compiled bindings in DataTemplates,x:Bind in templates requires x:DataType,x:DataType on DataTemplate for compiled bindings,{Binding} in item templates for large lists,"<DataTemplate x:DataType=""local:Item""><TextBlock Text=""{x:Bind Name}""/></DataTemplate>","<DataTemplate><TextBlock Text=""{Binding Name}""/></DataTemplate>",High,https://learn.microsoft.com/en-us/windows/uwp/xaml-platform/x-bind-markup-extension,uwp legacy,deprecated,2026-08-13
30,Performance,Profile with Visual Studio diagnostics,Measure before optimizing,Application Timeline and Memory Usage tools,Guessing at performance problems,VS Diagnostic Tools > Application Timeline,Optimizing without profiling data,Medium,https://learn.microsoft.com/en-us/visualstudio/profiling/application-timeline,uwp legacy,deprecated,2026-08-13
31,Threading,Use async/await for all IO,Keep UI thread responsive,async/await for file network and database operations,Synchronous IO blocking the UI thread,var file = await StorageFile.GetFileFromPathAsync(path);,StorageFile.GetFileFromPathAsync(path).AsTask().Result;,High,https://learn.microsoft.com/en-us/windows/uwp/threading-async/asynchronous-programming-universal-windows-platform-apps,uwp legacy,deprecated,2026-08-13
32,Threading,Use CoreDispatcher for UI thread access,Post work back to the UI thread from background,Dispatcher.RunAsync from background threads,Touching UI elements from background threads,"await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => Status = ""Done"");","textBlock.Text = ""Done"" from Task.Run",High,https://learn.microsoft.com/en-us/uwp/api/windows.ui.core.coredispatcher,uwp legacy,deprecated,2026-08-13
33,Threading,Offload CPU work with Task.Run,Keep compute-heavy work off UI thread,Task.Run for CPU-bound operations,Heavy computation blocking UI,var result = await Task.Run(() => ProcessData(items));,var result = ProcessData(items); freezing UI,High,https://learn.microsoft.com/en-us/windows/uwp/threading-async/asynchronous-programming-universal-windows-platform-apps,uwp legacy,deprecated,2026-08-13
34,Threading,Use IProgress for status updates,Report progress from background operations,IProgress<T> for progress reporting to UI,Polling shared variables for progress,var progress = new Progress<int>(p => ProgressBar.Value = p); await Task.Run(() => Process(progress));,while (!done) { await Task.Delay(100); check shared field; },Medium,https://learn.microsoft.com/en-us/dotnet/api/system.progress-1,uwp legacy,deprecated,2026-08-13
35,Adaptive,Use AdaptiveTrigger for responsive layouts,MinWindowWidth and MinWindowHeight triggers fire at standard breakpoints (640 small / 1008 medium),AdaptiveTrigger inside VisualState.StateTriggers with the 640 and 1008 breakpoints,Fixed layouts for a single screen size,"<VisualState.StateTriggers><AdaptiveTrigger MinWindowWidth=""640""/></VisualState.StateTriggers>",Single-column layout at all widths,High,https://learn.microsoft.com/en-us/windows/uwp/design/layout/layouts-with-xaml,uwp legacy,deprecated,2026-08-13
36,Adaptive,Design for multiple device families,Phone tablet desktop Xbox and HoloLens,DeviceFamily-specific views and resources,Desktop-only design ignoring other form factors,DeviceFamily-Mobile/MainPage.xaml for phone-specific layout,Fixed 1920x1080 layout,Medium,https://learn.microsoft.com/en-us/windows/uwp/design/layout/screen-sizes-and-breakpoints-for-responsive-design,uwp legacy,deprecated,2026-08-13
37,Adaptive,Use RelativePanel for adaptive positioning,Controls position relative to each other,RelativePanel for layouts that reflow at breakpoints,Absolute positioning or fixed margins,"<Button RelativePanel.Below=""title"" RelativePanel.AlignLeftWithPanel=""True""/>","<Button Margin=""0,60,0,0""/> calculated from title height",Medium,https://learn.microsoft.com/en-us/windows/uwp/design/layout/layouts-with-xaml#relativepanel,uwp legacy,deprecated,2026-08-13
38,Adaptive,Support multi-window with secondary views,Open detached views with CoreApplication.CreateNewView and ApplicationViewSwitcher,CreateNewView and TryShowAsStandaloneAsync for multi-document scenarios,Single-window assumptions when scenarios benefit from secondary views,"var view = CoreApplication.CreateNewView(); await view.Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => { /* set content */ });",Modal overlay used for content that should be a separate window,Medium,https://learn.microsoft.com/en-us/windows/uwp/design/layout/show-multiple-views,uwp legacy,deprecated,2026-08-13
39,Accessibility,Set AutomationProperties,Enable Narrator and screen reader support,AutomationProperties.Name on all interactive controls,Controls without accessible names,"<AppBarButton AutomationProperties.Name=""Save document"" Icon=""Save""/>","<AppBarButton Icon=""Save""/> without name",High,https://learn.microsoft.com/en-us/windows/uwp/design/accessibility/basic-accessibility-information,uwp legacy,deprecated,2026-08-13
40,Accessibility,Support keyboard and gamepad,All functions reachable without touch,Tab navigation XYFocus and access keys,Touch-only interactions,"<Button AccessKey=""S"" XYFocusDown=""{x:Bind OtherButton}""/>",No keyboard or gamepad support,High,https://learn.microsoft.com/en-us/windows/uwp/design/input/keyboard-interactions,uwp legacy,deprecated,2026-08-13
41,Accessibility,Support contrast themes,Respect system contrast themes (renamed from high contrast in Windows 11),ThemeResource brushes that adapt to contrast themes,Hardcoded colors that vanish under contrast themes,"Foreground=""{ThemeResource SystemControlForegroundBaseHighBrush}""","Foreground=""#444444""",High,https://learn.microsoft.com/en-us/windows/uwp/design/accessibility/high-contrast-themes,uwp legacy,deprecated,2026-08-13
42,Accessibility,Test with Narrator and Accessibility Insights,Validate screen reader and automation compliance,Regular Narrator walkthrough and Accessibility Insights scan,Shipping without accessibility testing,Accessibility Insights FastPass on every page,No accessibility testing before release,Medium,https://accessibilityinsights.io/,uwp legacy,deprecated,2026-08-13
43,Architecture,Use MVVM pattern,Separate View ViewModel and Model,ViewModel with INotifyPropertyChanged and ICommand,Business logic in code-behind,ViewModel bound via DataContext with commands,MainPage.xaml.cs with database calls and UI logic,Medium,https://learn.microsoft.com/en-us/windows/uwp/data-binding/data-binding-and-mvvm,uwp legacy,deprecated,2026-08-13
44,Architecture,Use Template Studio for scaffolding,Proven project templates with navigation and services,Windows Template Studio for new UWP projects,Blank project with manual boilerplate,Template Studio with MVVM Toolkit and navigation service,Blank App template building everything from scratch,Low,https://github.com/microsoft/TemplateStudio,uwp legacy,deprecated,2026-08-13
45,Architecture,Use dependency injection,Register services for testability,Microsoft.Extensions.DI for service resolution,Static singletons and manual construction,"services.AddTransient<MainViewModel>(); services.AddSingleton<IDataService, DataService>();",DataService.Instance or new DataService() everywhere,Medium,https://learn.microsoft.com/en-us/dotnet/core/extensions/dependency-injection,uwp legacy,deprecated,2026-08-13
46,Architecture,Keep platform APIs behind abstractions,Isolate WinRT APIs from business logic,Interfaces wrapping StorageFile FilePicker etc,Direct WinRT calls in ViewModels,IFileService wrapping FileOpenPicker and StorageFile,FileOpenPicker usage directly in ViewModel,Medium,https://learn.microsoft.com/en-us/windows/uwp/data-binding/data-binding-and-mvvm,uwp legacy,deprecated,2026-08-13
47,Lifecycle,Handle suspend and resume,UWP apps are suspended when not in foreground,Save state in OnSuspending and restore in OnLaunched,Ignoring app lifecycle losing user state,"Application.Current.Suspending += (s, e) => SaveState();",No suspend handler losing in-progress form data,High,https://learn.microsoft.com/en-us/windows/uwp/launch-resume/app-lifecycle,uwp legacy,deprecated,2026-08-13
48,Lifecycle,Use ExtendedExecutionSession for background work,Request extended time for unfinished operations,ExtendedExecutionSession for saving or uploads,Assuming background work completes after suspend,var session = new ExtendedExecutionSession { Reason = ExtendedExecutionReason.SavingData };,Long upload with no extended execution that gets killed on suspend,Medium,https://learn.microsoft.com/en-us/windows/uwp/launch-resume/run-minimized-with-extended-execution,uwp legacy,deprecated,2026-08-13
49,Lifecycle,Handle prelaunch,Apps must opt in to prelaunch via CoreApplication.EnablePrelaunch(true) starting in Windows 10 1607; check LaunchActivatedEventArgs.PrelaunchActivated to skip user-visible work,Opt in with EnablePrelaunch and skip heavy init when PrelaunchActivated is true,Performing full initialization or navigating during prelaunch,CoreApplication.EnablePrelaunch(true); if (e.PrelaunchActivated) return; // skip heavy init,Loading all data and navigating on prelaunch,Medium,https://learn.microsoft.com/en-us/windows/uwp/launch-resume/handle-app-prelaunch,uwp legacy,deprecated,2026-08-13
50,Testing,Unit test ViewModels,Test logic without UI framework dependencies,xUnit or MSTest on ViewModel methods,Testing only through the running app,[Fact] public async Task Load_PopulatesItems() { await vm.LoadAsync(); Assert.NotEmpty(vm.Items); },Manual testing by tapping through the app,Medium,https://learn.microsoft.com/en-us/dotnet/core/testing/unit-testing-best-practices,uwp legacy,deprecated,2026-08-13
51,Testing,Use WinAppDriver with Appium for UI tests,Automated UI testing for UWP (Coded UI Test was deprecated in Visual Studio 2019); WinAppDriver v1 is in low-maintenance mode and Appium 2 is the modern direction,WinAppDriver with Appium for end-to-end tests,Manual regression testing,"session.FindElementByAccessibilityId(""SaveButton"").Click();",Manual click-through testing before each release,Medium,https://github.com/microsoft/WinAppDriver,uwp legacy,deprecated,2026-08-13
52,Testing,Test on multiple device families,Behavior varies across phone desktop and Xbox,Test on device emulators and real hardware,Desktop-only testing,Test on Mobile emulator and Xbox dev mode,Only running on local desktop,Medium,https://learn.microsoft.com/en-us/windows/uwp/debug-test-perf/device-portal,uwp legacy,deprecated,2026-08-13
53,Architecture,Prefer WinUI 3 for new projects,UWP is maintenance-only; WinUI 3 with the Windows App SDK is the recommended path for new Windows apps,Use WinUI 3 with the Windows App SDK for every new Windows app,Start a new Windows app on UWP,New project with Microsoft.WindowsAppSDK and WinUI 3,New UWP project for a Windows app,Medium,https://learn.microsoft.com/en-us/windows/apps/get-started/,uwp legacy,deprecated,2026-08-13
54,Architecture,Plan migration to Windows App SDK,Maintain existing UWP apps while planning migration to WinUI 3 and the Windows App SDK; do not expand UWP as the foundation for new Windows development,Use the UWP migration guidance to plan an incremental migration or full port to WinUI 3,Continue major new-app investment on UWP without a Windows App SDK migration plan,Follow the UWP to WinUI 3 migration guide for existing apps,Start a new Windows app on UWP instead of WinUI 3,Medium,https://learn.microsoft.com/en-us/windows/apps/windows-app-sdk/migrate-to-windows-app-sdk/overall-migration-strategy,uwp legacy,deprecated,2026-08-13
55,Lifecycle,Use a deferral when saving async state on suspend,Suspending grants only ~5 seconds before the OS may terminate; await work needs SuspendingOperation.GetDeferral and Complete or save returns before it finishes,GetDeferral around async save calls and Complete in finally,Async work that returns the suspending handler before completion,"async void OnSuspending(object s, SuspendingEventArgs e) { var d = e.SuspendingOperation.GetDeferral(); try { await SaveAsync(); } finally { d.Complete(); } }","async void OnSuspending(object s, SuspendingEventArgs e) { await SaveAsync(); } // handler returns before save completes",Medium,https://learn.microsoft.com/en-us/windows/uwp/launch-resume/app-lifecycle,uwp legacy,deprecated,2026-08-13