1. A system for allocating control of a user interface in a retail device, comprising: at least one processor configured to execute a director service application for regulating control of a plurality of point-of-sale (POS) applications to the user interface of the retail device based at least in part on a predefined set of business rules; and a memory coupled to the at least one processor for storing instructions related to the director service application, wherein the director service application is configured to determine whether to terminate control of the user interface from a first POS application of the plurality of POS applications in favor of a second POS application of the plurality of POS applications based at least in part on a request from the second POS application for the first POS application to relinquish control of the user interface.