I believe the latest versions of iOS just work from the browser, you only need to install the app for older versions of the OS. I don't know what technology th

I believe the latest versions of iOS just work from the browser, you only need to install the app for older versions of the OS. I don't know what technology they're using, but when I scanned the QR code it launched (downloaded?) an iOS app of sorts with one tap, similar to the way Google tried Instant Apps a few years back. Didn't even need to double tap the power button like usual.