Apple, Google release smartphone technology to notify users of possible exposure to coronavirus

"Some privacy advocates have favored the Google-Apple approach because it offers more privacy and security. But others, including Ryan Calo, a law professor who co-directs the University of Washington's Tech Policy Lab, said he is concerned about its effectiveness if people get too many false alerts asking them to quarantine themselves. He said public health agencies would be better off being able to track location with careful safeguards.

Calo said Google and Apple have been more upfront about the limitations of their model, but he said he's still worried some governments will treat it as a substitute for crucial investments in free, widespread testing and hiring an army of human contact tracers.

"We're just not going to get out of this global pandemic with a clever app," he said."