Wow thanks for the pointer to Eto.Forms - cross platform Windows Forms including Linux, OSX, and iOS (but not yet Android) is pretty awesome to hear about
Yeah, there's actually quite a few different cross platform projects that support basic to more complex forms. As a fan of Material Design and "The UI formerly known as Metro" I wish more of them would adopt one or the other as a baseline though.
I just am most familiar with Eto off the top of my head... mostly because of PabloDraw.
