How about the NFC (Apple/Samsung Pay) workflow: - Tap phone (that's already in your hand because you were aimlessly swiping while standing in line) to terminal

How about the NFC (Apple/Samsung Pay) workflow: - Tap phone (that's already in your hand because you were aimlessly swiping while standing in line) to terminal with finger on fingerprint reader while cashier is ringing up items - Tap confirm and sign once all items rung up