In a busy shop with a small team, stamping becomes an interruption. Kiosk mode removes it.
Create my free cardIn a bakery at lunchtime or a gym at seven, nobody is going to drop what they are doing to scan cards. The programme gets used for a month and then quietly abandoned.

You leave a tablet or an old phone on the counter showing a code. The customer scans it with their phone and their stamp lands. The code changes every 30 seconds.
Thirty seconds. Long enough to scan while standing there, too short to photograph and send to a friend who never came.
You set how many stamps one person can give themselves per day at the kiosk. Usually one.
You can run the kiosk and still stamp by hand when you need to. The same rules apply to both.
Kiosk mode trusts that whoever scans is standing in your shop. With a rotating code and a daily cap the fraud is marginal, but it is not zero: do not use it where the reward is expensive.
No. Any old phone with the browser open will do. All it needs is a screen and power.
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