Paper worked. The trouble is it gets lost, gets wet, stays in the other jacket, and nobody knows how many stamps are on it.
Create my free cardA paper card is cheap and easily lost. When the customer loses it they also lose the appetite to start again, and you lose the only sign you had that they were coming back. It also tells you nothing: how many are halfway, who stopped coming, how many finished.

You put a QR code on the counter. The customer scans it, leaves a name and an email, and the card lives on their phone. No app to install. Every time they come back your team scans the card and the stamp lands instantly.
The card lives at a link and in the phone’s wallet. New phone, same email, same card, same progress.
Your colours, your logo, your words. Not a generic tool with your name stuck on top.
Every stamp is recorded with the time, the location and who added it. That is what later tells you who comes back and who does not.
It is no use for a business people buy from once in a lifetime. A stamp card needs repetition: if your customers do not naturally return, that is the problem to solve first.
No. They scan a QR code and the card opens in the browser they already have. If they want, one tap saves it to Apple Wallet or Google Wallet.
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