Citizen is a mobile app that sends users location-based safety alerts in real time. It allows users to read updates about ongoing reports, broadcast live video, and leave comments. The app uses radio antennas installed in major cities to monitor 911 communications, with employees filtering the audio to generate alerts. In March 2020, Citizen added the COVID-19 digital contact tracer SafePass. The app is currently available for iOS and Android devices in 20 cities, including New York City, the San Francisco Bay Area, Baltimore, Los Angeles, Philadelphia. Detroit, Indianapolis, Phoenix, Cincinnati, Chicago, Minneapolis, Saint Paul, and Cleveland.
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