On Friday, Google and Apple announced a surprise collaboration to integrate contact tracing for COVID-19 into iOS and Android. That first phase of this plan is coming next month, but deeper OS-level integration is also planned. In rolling out these features to Android, Google will be bypassing the platform’s usual update process by leveraging Play services.
What is contact tracing?
Contact tracing is usually an analog process where public workers ask an infected individual to list all the people they’ve come into contact with. Health departments then ask those people to watch out for symptoms and isolate them. The COVID-19 pandemic has already seen some countries leverage carrier-derived location data to contact trace.
Apple and Google are working to provide their own cross-platform solution that better preserves privacy. For example, your location data or identity is never revealed in the process:
When two people are in close range, their phones will exchange anonymous identifiers that change daily. If an individual gets diagnosed with COVID-19, they can have their device transmit a list of everybody they’ve been in contact with to the cloud.
Meanwhile, the second person’s phone will periodically download a list of everyone that has tested positive in their area. If a match occurs, they will be notified and prompted to contact health authorities.
Contacting tracing needs to be implemented on the OS-level to ensure that it’s constantly running in a power-efficient manner.
Phase 1 in May will see Google and Apple release an API that public agencies can use to build a contact tracing app for their population. This will be accompanied by an OS update to support those apps. Those governmental authorities will be the only groups granted access to the API as they are the ones permitted to perform non-digital contact tracing.
In the coming months, Phase 2 will be more ambitious in that the public will not need to download a new app. Built into the OS, users will be able to start contact tracing by just heading into their phone’s settings and opting in.
From this point onward, your phone will broadcast the anonymous identifiers to other nearby phones. If there’s a positive, Android and iOS will be able to directly alert you and then prompt an app download.
According to a company representative today, Android will be leveraging Google Play services to ensure that devices get contact tracing capabilities without a full OS update. Play services are always kept up-to-date in the background and provides basic functionality that powers Google apps, security, locating lost devices, and signing in.
This approach also helps older phones that no longer receive full OS updates gain this crucial functionality. Specifically, contact tracing via Play services will be available on Android 6.0 Marshmallow devices and newer.
This project between the companies’ engineering and health teams started two and a half weeks ago, with both working hard to meet the first deadline.