When the coronavirus broke out in China, the surveillance state went into overdrive. Thermal scanners were installed in train stations, a color-coded surveillance app now tells citizens whether they can leave their homes, and millions of security cameras revealed who was breaking quarantine.

While it's highly unlikely that we'd go that far in the U.S., researchers here are scrambling for more comprehensive and granular data, raising the question of what kind of personal information we should collect in a time of crisis

Apple and Google say they can help end the quarantines. The tech giants have teamed up to build a tool that will alert smartphone users if they've been in contact with someone who has coronavirus. This is called "contact tracing" and it's helped a number of East Asian countries slow the spread.

For it to work though, first we need significantly more testing. And then, the public needs to trust the promise that tech companies aren't saving any sensitive health information. While what's been proposed is an opt-in tool, concerns swirl that it could eventually become mandatory, and that it will prove difficult to roll back data-gathering efforts after the crisis passes.

But if we're going to get the economy up and running again, a sophisticated contact-tracing tool could be a major part of the solution.