This is the real SwapDeck interface with made-up accounts. Click around: switch accounts, open the Library, set up a game and press Play.
It's all pretend: nothing here touches Steam or your PC, and nothing leaves your browser.
SwapDeck is a desktop app, so this demo works best on a computer.
SwapDeck is still running in the tray. Click its icon in the bottom-right corner to switch accounts or start a recent game, or reopen the window from there.