Unfortunately CrowdedYet has been forced to shut down. If you are looking to see how busy buildings on your campus are head to waitz.io/[school]. For example www.waitz.io/waterloo. (If you go to the University of Waterloo you'll see they replicated this code and display it on the TV above the elevators in DP).
Below is a historical view, it's not real data (please don't come after me again).
Universities/Colleges (Historical View)
Cease and Desists
Initial Notice
Follow-up Notice
Just to make it clear, I appreciate how respectful Occuspace was in this process. To see the support received from students, check this Reddit post