It's a game. It's UI is full screen and completely divorced from "standard" UI elements (WIMP, etc).
You can call it a desktop app, and you'd be correct in the most pedantic sense, but then every web app is also a desktop app since you run it on a desktop.
You can call it a desktop app, and you'd be correct in the most pedantic sense, but then every web app is also a desktop app since you run it on a desktop.