He said that the age of most of the visitors means that use of the app would be high.
"The majority of the people at Mardi Gras will be young, tech savvy, digital natives who would have no problem in downloading and using the Covid Tracer app.
"While I expect most people will be doing the right thing and using the contact tracing app or another method that works for them, for those that aren't or are forgetful there is no problem in calling on them to do so."
He also called on revellers to practice good hygiene and consider wearing a face covering.
"As the Mardi Gras tradition includes dressing-up there is a great opportunity for people to decorate their face mask," he said.
Locals' response was mixed, with some praising the mayor's advocacy and others seeing it as an over-reach.
"Mardi Gras shouldn't even be happening, 7000 drunks being asked to record their visits, bloody joke," wrote one disgruntled local.
Others noted that the mayor had no power to enforce the request and asked if he was going to provide everyone with a phone capable of using the app.
But some supported the move, saying Cameron was "ensuring the district is protected".