The University of Nottingham’s AtomicOrchid is a location-based mixed reality game which plays with the idea that a dirty bomb has exploded on the campus. A search-and-rescue team is despatched to pick up people from the radioactive zone. They are equipped with smartphones which connect them to their command post, letting them stream back video and field data, chat with other team members, and gain access to map displays as well as Geiger counter reading and health status check. In this scenario, the phone is more than a comms tool. It has become a sensor for probing the electro-magnetic spectrum, a sort of digital dowsing rod. For a different application of the idea, see
http://waag.org/en/project/digital-dowsing-rod