The Technology Behind Google And Apple's COVID-19 Contact Tracing Partnership
Rather than relying GPS, which can have privacy implications concerning location data, Apple and Google will be deploying a Bluetooth Low Energy-backed contact tracing platform. With this system, iPhone and Android devices will be able to send Bluetooth identifier beacons, and in return receive signals from other devices (these identifier beacons would be sent in 5-minute intervals).
Using a special app, someone that tests positive for COVID-19 would be able to [voluntarily] input their test result, which will then upload two weeks’ worth of keys that his or her device has received to the cloud. Anyone that was in close proximity to the “infected” person during that time period – and is using an officially sanctioned app that will download those broadcast beacon keys -- will receive a notification alerting them that they could have potentially been exposed to COVID-19.
You can see the embedded diagrams for how this would work in practice, and you can also look a whitepaper [PDF] that the two companies have drafted which describes the underlying technology behind this contact tracing platform.
Both companies are touting the privacy of this initiative, with their privacy declaration stating:
The Contact Tracing Bluetooth Specification does not require the user’s location; any use of location is completely optional to the schema... In any case, the user must provide their explicit consent in order for their location to be optionally used. Rolling Proximity Identifiers change on average every 15 minutes, making it unlikely that user location can be tracked via Bluetooth over time.
“All of us at Apple and Google believe there has never been a more important moment to work together to solve one of the world’s most pressing problems,” the two tech giants write. “Through close cooperation and collaboration with developers, governments and public health providers, we hope to harness the power of technology to help countries around the world slow the spread of COVID-19 and accelerate the return of everyday life.”
The aforementioned interoperable APIs will be released in May, and apps for each respect platform – iOS and Android – will be available to download from the App Store and Google Play.