“…The genres of applications we have examined include messaging systems, such as cell phones, instant messenger, SMS, and messaging within [52] and between homes [37]; guides for exploration and navigation [4,54]; finders for finding people, places, or things [7,31]; group awareness displays [20,31]; augmented-reality games [25,29]; contextual tagging and retrieval, including personal memory aids [12,46,59], associating topical information with places [13,24,56,62]; situational realtime information (such as local weather or traffic); and enhanced safety for individuals and emergency responders [26,51].…”