When a player found a puzzle in the city, he or she submitted its code name (printed in a fortune cookie design on every puzzle) through this web app. This let game control monitor teams' progress, and occasionally the web app dispensed additional information to the players.
Midnight Madness is about being in the city, not about playing a video game, so for players tempted to spend all night staring at the app, we wanted the screen to be as unrewarding as possible. So it's an endless road.
See a video demo of it here: https://www.youtube.com/watch?v=CNXBP9sYsXU.