https://www.siliconvalley.com/2021/04/13/vaccine-passport-apps-are-about-to-be-everywhere-it-could-get-complicated/

As the vaccine rollout continues to accelerate and the broader US economy prepares to reopen, talk of vaccine verification apps has heated up.

Tech companies, health care providers and even retail stores are working on digital health pass apps that will allow users to show proof of vaccination before entering events and businesses. The state of New York is already scanning IBM’s Excelsior app at the door of venues such as Madison Square Garden ahead of sporting events; if you’ve tested negative for Covid-19 or received a vaccine, you can watch a Rangers hockey game in person.