Friend comes with a complete, responsive Window management across devices. On desktop and laptops the interface behaves almost the same. On mobile the window management changes to focus on one window at a time.
Friend applications use a couple of classes to manage their user interface:
The View class is the most used class in applications. A View generates a new window in the Friend Workspace.
The Widget class is a bit like the View class, but has both a different visual appearance and a slightly different behaviour.
The Screen class is used to create new screens in the Friend Workspace. The screen class is there to help you organize your View windows on a separate spatial area, as an alternative to just opening a View window on the default Friend Workspace screen.
A file dialog is a special class. It shows up in a View window and gives the result of user interaction in a callback.