Demo mode is the default mode for the guest (unregistered) users to use the website's exercises.
In the Demo mode all the exercises' functionality is available including settings and different game types.
However in the demo mode you can not save the progress you've done on the exercises and therefore you don't have the access to the game statistics section of the website. You also don't get your result in the top results ranking board.
Every time you are doing an exercise in the Demo mode you'll see the warning message at the bottom of the screen.
Registering the account allows you to:
There is one limitation that applied to free registered accounts: on the exercise start you'll get an exercise start-up dialog in front of you, making you wait for the exercise from 10 to 20 seconds.
To eliminate the start-up dialog and start the application immediately you may get the Premium Account by paying a small fee on the go premium page.