Architecture that facilitates the broadcast of a custom signature message to one or more portable wireless devices that enter an associated area of coverage. A subscriber to the service pays a premium to have the rights to broadcast the custom message to all users who enter and/or leave the cell. The rights can be exclusive for a coverage area over an extended period of time. For example, a company can subscribe to broadcast a single message to all wireless users who enter a cell for a period of one year. Subscriber account information includes quality-of-service (QoS) data that indicates the highest level of service such that when a wireless device is detected as entering the cell, only the subscriber's message will be broadcast to all users for a brief time.