The demo merchant waits for Binance to approve our B402 application, so paying is switched off right now. See Status.
1
Open Pay
In the bottom bar, in Card mode. The demo merchant creates an order with a price in USD1.
2
Tap Pay with Face ID
Your passkey unlocks the card’s key on your phone, and the key signs a transfer of exactly that amount to the merchant.
3
Done
The merchant hands the signed transfer to B402, which sends it on BNB Chain and pays the network fee. The screen says No BNB used. Binance paid the network fee. The payment shows in your History.
What you sign
One transfer of USD1, for one amount, to one address, valid once. Signing it can’t move anything else from your card. Under the hood it is an EIP-3009transferWithAuthorization; see Payments.