Covid Watch has been working for two months on an app and protocol that will protect users' privacy while reducing the spread of COVID-19. Today, the world’s leading tech companies joined that mission.
After discussions with Covid Watch and our partner organizations, Apple and Google announced today that they are working together for the first time on a protocol that will alert users if they have been exposed to the coronavirus.
The specifications for their APIs, to be released in May, make it clear that the standard going forward for digital contact tracing will respect privacy.
“This is a game-changer,” said Tina White, executive director of Covid Watch, a nonprofit operating in collaboration with Stanford University. “These tools allow for the kind of communication between devices that is required for COVID-19 mobile app interventions. And they will make privacy the cornerstone of future efforts.”
The plan announced today is nearly identical to Covid Watch’s Temporary Contact Number protocol, also known as TCN. This protocol ensures the anonymity of users who send and receive contact alerts for COVID-19. Under TCN, the connections cannot be traced back to a specific device or user identity.
This makes TCN distinct from centralized digital contact tracing – like Singapore’s TraceTogether – under which users and their contact networks could be tracked by the government, significantly eroding privacy laws and norms in many jurisdictions.
On March 17, Covid Watch volunteers open sourced a Bluetooth communication protocol – the first to allow for communication between Apple’s iOS and Google’s Android operating systems. Covid Watch then released a white paper describing the privacy model that has since become the broader TCN protocol.
Many open-source contact tracing efforts have converged on this privacy-focused contact alert system, leading to the formation of the TCN Coalition.
Over the past two weeks, Covid Watch has met with Apple and Google to discuss the TCN protocol, and discussed with Apple in detail the changes needed to implement TCN effectively. Among other issues, sending contact alerts via Bluetooth requires apps to be running in the background on iOS.
“These changes address problems we’ve encountered as we’ve poured effort into creating contact alert protocols,” said Covid Watch co-founder James Petrie. “Looking at what Google and Apple have planned, you can see the influence of this open-source community. We’re excited and grateful that these two leading tech companies have chosen to help us set precedents that protect privacy.”
“We look forward to incorporating these tools from Apple and Google,” said Covid Watch co-founder Zsombor Szabo.
Oxford university epidemiologists recently showed that digital contact tracing could play a critical role in enabling regions to come out of lockdowns. If 60 percent of people opt into functional, secure contact alerts, it could stop the virus, when implemented in addition to traditional contact tracing, testing, and responsive isolation.
“The sooner everyone can all make use of these APIs and protocols, the sooner the world can stop the spread of the disease. We need to move quickly and advocate for apps that use these privacy-preserving protocols to be adopted,” White said.
Covid Watch will continue to advance these privacy-focused protocols via the Covid Watch app, which will be released later this month, and through collaboration with other apps implementing this protocol. This is an exciting step in the right direction: away from surveillance, and towards safety and privacy.