US Patent 9311419 System for data card emulation

An improved system for data card emulation involves a watch that can emulate any one of multiple data cards corresponding to multiple entities. The watch includes a memory for storing bar code information corresponding to data cards of the multiple entities. It provides an interface for identifying an entity and a display for displaying a bar code corresponding to a data card of the entity. The interface may include at least one of a bar code reader or a bar code emulator. The interface may include at least one of a magnetic stripe reader or a magnetic stripe emulator. The interface may receive a transmission such as a pulsed light transmission or a radio frequency transmission.