A method is provided so mobile devices can communicate through their wireless data services to a public computer network, which are normally deactivated when not in use. A first device calls a second device over a wireless voice service. The first device activates its wireless data service and sends a request to communicate with the second device to a server on the public computer network. Without answering the voice call, the second device determines an ID of the first device. The second device then activates its wireless data service and sends a query to the server to determine if the first device desires to communicate over the public computer network. The server responds to the request and the query by setting up a network connection between the first and the second device over the public computer network so they can exchange data packets.