Windows App SDK

Windows App SDK is Microsoft’s modern desktop app platform layer. It delivers APIs through NuGet and runtime packages instead of waiting for every feature to ship only with the OS.

What It Provides

AreaExamples
UIWinUI 3 controls, XAML, Fluent Design
App lifecycleActivation, instancing, restart, notifications-related activation
WindowingAppWindow, presenters, title bar support
NotificationsLocal app notifications through Microsoft.Windows.AppNotifications
DeploymentRuntime packages, bootstrapper, Deployment API
Resource managementModern resource APIs and package-aware behavior

Release Channels

Use stable for production apps. Preview and experimental channels are for testing upcoming features and should not be the default for solo-dev shipping work.

Recheck Latest Windows App SDK downloads before choosing versions. During this pack run, the latest stable version seen was 2.3.1, but that is intentionally not a durable recommendation.

Relationship To Windows SDK

TermMeaning
Windows SDKOS SDK: headers, metadata, tools, base Windows API surface
Windows App SDKApp platform APIs shipped through NuGet and runtime packages
Windows App RuntimeRuntime packages used by framework-dependent Windows App SDK apps
WinUI 3UI framework included in Windows App SDK

Supported OS Baseline

Microsoft docs describe Windows App SDK/WinUI 3 as supporting Windows 10 version 1809 and later. Project templates may use newer target framework or target platform values. Follow the current template and release notes.