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Xamarin.Forms.Platform.Avalonia

Xamarin Forms platform implemented with Avalonia (A multi-platform .NET UI framework)

Xamarin.Forms

Xamarin.Forms provides a way to quickly build native apps for iOS, Android, Windows and macOS, completely in C#.

Read more about the platform at https://www.xamarin.com/forms.

Avalonia

Avalonia is a WPF-inspired cross-platform XAML-based UI framework providing a flexible styling system and supporting a wide range of OSs: Windows (.NET Framework, .NET Core), Linux (GTK), MacOS, Android and iOS.