https://www.vox.com/recode/22736276/new-york-state-vaccine-passport-excelsior-pass > A key feature of the Excelsior Pass app is rarely used. > New York’s Excelsior Pass is getting more popular. Since it launched in March, the digital vaccine platform has issued millions of passes, which allow people to display proof of vaccination or negative test results via an app developed by the state. But not many businesses are using the Excelsior Pass’s signature feature: a scannable QR code that can quickly verify customers’ vaccination status by checking state records.