The Plan
Apple and Google are planning to release new APIs in May that will allow official apps from public health authorities to interact with the system, giving developers from those organizations a chance to update their apps and test the integration and leverage it for their own contact tracing features.
At this stage, it will be possible for official apps to perform contact tracing, but much like Singapore’s TraceTogether app, it will only be available for those who are using the relevant apps, meaning that you won’t know if you may have come into contact with an infect person unless they also happen to have been running a compatible app.
Following that, however, Apple and Google will work together to build the Bluetooth-based contact tracing in at the operating system level, and although participation will still be voluntary, it will allow more users to opt-in through a much simpler process, as well as allowing more government and health apps to tie into the data.