The purpose of this page is to test keyboard event handlers, specifically whether these keyboard events can be triggered from a standard on-screen keyboards on mobile devices.
And the music recommended here is pretty good!
Instructions
With focus on the "My favorite albums" input field:
Press down or right arrow to reveal an album (it will be added at the end of the list).
Press left or up arrow to hide the last album (it will be removed from the end of the list).