Not on the surface? In the shell you have select "activities" that you can choose, and if the "activity" you chose is a standard linux app, or a explorer-style

Not on the surface? In the shell you have select "activities" that you can choose, and if the "activity" you chose is a standard linux app, or a explorer-style application (i.e. I remember I was still able to run Nautilus?) you would see file structure. But you would be able to use it without encountering "a file" or "a folder". I remember window management being minimalistic, apps went full-screen, there might have been a switcher.