Earlier this month, Apple and Google have decided to work together to build a COVID-19 tracking system. Now, the companies confirmed that testing will start today.

The tracking system will be using Bluetooth technology to help track potential COVID-19 cases.

Here’s an example of how it works. Smartphone A tracks smartphones B, C, and D via Bluetooth. This could be happening in any public setting, and of course, within a certain range.

If the user of smartphone A tests positive for COVID-19, the API will allow public health authorities to inform users of smartphones B, C, and D, based on tracking data from smartphone A.

The other three users should then go for a COVID-19 test themselves, just to make sure they’re not affected.

That’s basically how it works, from my understanding. Of course, private information such as the patient’s identity and location data are not recorded by the tracking system.

A full release of the tracking system is expected to arrive by May.

Apple also released a beta version for Xcode 11.5 and the third beta of iOS 13.5. Both betas contain new tools to help build iOS apps with the API and code to run future apps from public health authorities.

Both Apple and Google will also be releasing a sample code on Friday to show developers how to build apps using the system.

It’s not made clear if the tracking system will be only released in the US first when it launches. However, it has been mentioned that the system will be rolled out to other countries as well.