California residents now have one more tool in the fight against COVID-19. Starting today, smartphone users can sign up for CA Notify, which can send an alert if you’ve been around someone who later tests positive for the virus.
Here’s how it works: Users start by opting in to the voluntary system, either by activating a setting on your iPhone or installing an Android app. Once it’s set up, any time you leave the house, make sure you have Bluetooth activated. The system will ping other devices with CA Notify enabled and create a log of other devices that came within six feet for a period of 15 minutes or more, considered the highest-risk type of exposure (though by no means the only type of exposure that can result in infection).
If a user of the system ever receives a positive test result, they can alert the app anonymously using a private code received from the California Department of Public Health. CA Notify will then text owners of devices that came into contact with the patient to let them know they may want to get tested themselves.
What CA Notify is not is a contact tracing app like the ones deployed in Korea or Singapore. Officials say the app retains no identifying information about anyone who uses it and has no mechanism for contacting any other individuals you may have been in contact with other than the few alerted via their devices. CA Notify also doesn’t do anything to track where a particular user goes or the identities of anyone they are around.
Because the system is entirely voluntary and limited only to people who have smartphones and choose to run the app–and then only works as an alert when people who receive positive results choose to reveal that information to the system, which is not required–just switching on CA Notify certainly can’t take the place of any other health protocols. But, if enough people use it, it could send people to get tested who otherwise wouldn’t know they had been exposed and that, in turn, could chip away at the spread of COVID-19.