If approved, the system could be distributed to approved health organisation’s apps for iOS and Android phones that make up the majority of smartphones globally. The voluntary opt-in to the system would use the BLE tech built into smartphones to ping other smartphones in close proximity and store user-specific logs of proximity data.
The idea is if a person comes down with Covid-19, they log in the app that they are infected. Everyone whose smartphone had been close enough to that person’s recently would then receive a notification that someone they’d been near to has tested positive. Those people would also receive information on what to do next from their local health authority.
Despite the united front, there are privacy concerns associated with setting up a proximity contact tracing system like this. It’ll mean companies have to secure the data of potentially millions of people, and safeguard that data from harm’s way. Apple and Google said that their system does not collect “personally identifiable information or user location data” and is only used to alert you with regards to proximity to those who log themselves as positive.
Phones are linked together after broadcasting anonymous keys over Bluetooth, and these keys cycle every 15 minutes to help preserve privacy. Additionally, the companies claim the list of those you’ve been in contact with, which is anonymised, never leaves your phone.
The system would act only as a notifier of potential contact. A notification wouldn’t guarantee you were at risk and could cause panic. For example, you’d technically receive the same notification if you sat next to someone on the train for an hour or if you never came into contact with someone but were close to them through an apartment wall.
With no way of identifying the person who tested positive who you were near it won’t be a perfect system, but it will help contact tracing efforts using the technology of a device most people carry. But the privacy implications will be studied very keenly.