1. A method employing a user's portable device, the device including a display and a sensor module, the method including the acts: presenting a payment user interface on a display, the user interface identifying plural virtual wallet cards including plural payment service cards, said payment service cards representing plural possible payment services including at least one of American Express®, VISA® and MasterCard®; receiving user input selecting a desired one of said payment services for issuing a payment; generating sensor-based authentication data, said generating being performed using a particular apparatus, namely a user smartphone including said display and a sensor, the sensor being selected from the group consisting of a barometric sensor, a temperature sensor, an audio sensor, an image sensor, a magnetometer, an accelerometer, and a gyroscope, said authentication data being derived in part based on data from said sensor; presenting artwork using the display, the artwork indicating the selected one of said payment services and including a logo for the American Express®, VISA® or MasterCard® payment service; and providing information, including both the sensor-based authentication data and data corresponding to the selected payment service, from the smartphone to a cooperating point of sale system, in connection with issuing a payment.