This framework can be used to build applications that run across multiple platforms using their native toolkit, with an easy to use API. This will make your applications look and work as a native application on all platforms, using a single UI codebase.
For advanced scenarios, you can take advantage of each platform’s capabilities by wrapping your common UI in a larger application, or even create your own high-level controls with a custom implementations per platform.
This framework currently supports creating Desktop applications that work across Windows Forms, WPF, MonoMac, and GTK#. There is a Mobile/iOS port in the works, but is considered incomplete.
This framework was built so that using it in .NET is natural.
https://github.com/picoe/Eto
origin - https://www.pipiscrew.com/?p=19290 eto-forms