If stamping takes longer than taking the money, nobody stamps. That is the only test that matters.
Create my free cardAt eight in the morning with six people queuing, any extra step gets skipped. A loyalty programme that needs an app opened, a customer looked up and two confirmations stops being used within a week.

Your team opens the scanner in their phone’s browser, points it at the customer’s QR code, and the stamp lands. No app to install, no password to remember every shift.
If the internet drops, the scanner keeps the stamps and sends them when the connection comes back. Nobody misses a stamp because of the wifi.
Every scan carries a unique key. Tap the button twice and the stamp is still one.
Each stamp records who added it and where. Not to police anyone — so you can answer when a number looks wrong.
The scanner needs a camera and the browser’s permission. On a very old phone it can be slow; kiosk mode with an on-screen code covers those cases.
It is the better way, and the Business plan includes several. That is how you know who stamped what. A shared account works too.
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