Apple and Google have released technology for pandemic apps that will automatically notify people if they might have been exposed to the coronavirus.
22 countries and several U.S. states are planning to build voluntary phone apps using their software. It relies on Bluetooth wireless technology to detect when someone who downloaded the app has spent time near another app user who later tests positive for the virus.
The identity of app users will be protected by encryption and anonymous identifier beacons that change frequently so some governments have said the tech giants' privacy restrictions will be a hindrance because public health workers will have no access to the data.
The companies said they're not trying to replace contact tracing, a pillar of infection control that involves trained public health workers reaching out to people who may have been exposed to an infected person. But they said their automatic "exposure notification" system can augment that process and slow the spread of COVID-19 by virus carriers who are interacting with strangers and aren't yet showing symptoms.