One-tap identification, sometimes called single-tap, is the flow where a single tap on the payment terminal does two jobs at once: the payment card is read, and the wallet pass on the same phone or watch is read alongside it. The member is identified in the same gesture that pays, with no extra step for the shopper and nothing for staff to ask.
Technically, the terminal performs a card acquisition that polls for both the payment method and the pass in one tap. The point of sale learns who is standing at the till before the payment completes, which means discounts, points and member pricing can be applied to that very purchase, not credited after the fact.
This is the flow that closes the gap loyalty programs usually leak through. When identification is a separate step, a share of members skip it at every visit and those purchases never connect to a profile. When it rides on the payment tap, identification happens at the same rate as payment itself.
One-tap identification requires a terminal that supports reading wallet passes during payment, and support varies by terminal vendor and wallet. Where a till cannot run it, two-tap identification delivers the same recognition with one extra tap, and a pass can also carry a QR code or barcode that works on scanners merchants already own. All three routes identify the same member; the hardware at each till decides which one runs.