Apple and Google’s Exposure Notification System now publicly available

Public Health Authorities can now make use of the API in their apps

Apple and Google announced that its Exposure Notification System will release publicly through software updates starting May 20th.

The companies said that with the updates, public health agencies (PHAs) around the world can start deploying apps that make use of the system. Further, the API released by the companies is the result of feedback received from hundreds of conversations with PHAs, NGOs, academics, government officials and privacy experts from dozens of countries, company representatives said.

For those unfamiliar with the Exposure Notification System and API, Apple and Google began work on the project several weeks ago. The goal was to design an interoperable system that would work across Android and iOS smartphones. The system would be able to log proximity to other people and alert users if one of these ‘exposure’ events was with someone who tested positive for COVID-19.

The Exposure Notification System uses Bluetooth Low Energy (LE) technology to share random codes with other nearby smartphones. The codes can’t identify users and remain stored on the phone. When someone tests positive for COVID-19, they upload their codes through an app provided by their country, province or state’s PHA. Other smartphones can then access those codes and check for matches against the codes stored locally on those devices. The system will notify the user if it confirms a match and provide details about what to do next.

MobileSyrup has extensively covered the details of the Exposure Notification System as Apple and Google have released details about it. You can access prior coverage below, which includes more in-depth explanations of the underlying technology.

Phase one of the system rolling out now

Apple and Google said that as of May 20th, several U.S. states and 22 countries across five continents requested and received access to the API. Both companies expect more to join in the coming weeks.

It’s not clear if Canada was among the countries that requested access.

The first phase of the project will rely on PHAs release apps to take advantage of the API. The Exposure Notification System itself forms the backbone of the platform and should make the data interoperable between PHAs and apps. Further, both companies have provided sample apps to help PHAs develop their solutions.

Apple and Google both stress that the Exposure Notification System is not a ‘silver bullet,’ nor is it meant to replace traditional contact tracing. Instead, the system is meant as another tool for PHAs in combatting COVID-19.

Throughout the process, both companies gathered feedback and released multiple beta versions of the software. Additionally, they posted public documents that include Bluetooth, cryptography and API specifications to help PHAs and developers.

The second phase will build the functionality directly into the operating system of both smartphone platforms. That means users will not need to download a third-party app to participate in the system.

Feedback helped shape the system

Finally, the two companies detailed some of the final adjustments made to the system that came as a response to feedback received from PHAs.

First up, the Exposure Notification API will allow PHAs to define what constitutes an exposure event. It will also allow PHAs to determine the number of exposure events and individual has had. Additionally, the API allows PHAs to factor the transmission risk of positive cases into their definition of an exposure event. Finally, a combination of the API and data that users voluntarily choose to input into the app will allow PHAs to contact exposed users.

Apple and Google said that the goal of conversations with PHAs was to find the best way to meet their needs for technological support while also respecting user privacy, consent and control.

Further, the companies say they will not monetize any data that comes out of the API. On top of that, the API’s use is limited to PHAs.

Apple, Google detail goals behind the system

Apple and Google provided the following statement regarding the Exposure Notification API:

“One of the most effective techniques that public health officials have used during outbreaks is called contact tracing. Through this approach, public health officials contact, test, treat and advise people who may have been exposed to an affected person. One new element of contact tracing is Exposure Notifications: using privacy-preserving digital technology to tell someone they may have been exposed to the virus. Exposure Notification has the specific goal of rapid notification, which is especially important to slowing the spread of the disease with a virus that can be spread asymptomatically.

“To help, Apple and Google cooperated to build Exposure Notifications technology that will enable apps created by public health agencies to work more accurately, reliably and effectively across both Android phones and iPhones. Over the last several weeks, our two companies have worked together, reaching out to public health officials scientists, privacy groups and government leaders all over the world to get their input and guidance.

“Starting today, our Exposure Notifications technology is available to public health agencies on both iOS and Android. What we’ve built is not an app — rather public health agencies will incorporate the API into their own apps that people install. Our technology is designed to make these apps work better. Each user gets to decide whether or not to opt-in to Exposure Notifications; the system does not collect or use location from the device; and if a person is diagnosed with COVID-19, it is up to them whether or not to report that in the public health app. User adoption is key to success and we believe that these strong privacy protections are also the best way to encourage use of these apps.

“Today, this technology is in the hands of public health agencies across the world who will take the lead and we will continue to support their efforts.”