Suggest HN: Google, Apple and FB work together to stop coronavirus spread

To limit the spread of coronavirus, in China they have been using widespread facial recognition technology to track who has been near who. From this you can download an app and be informed if someone you have been near has it. In the west we do not have this in place, but nearly everyone in the west has a smart phone running iOS or Android (with FB, WhatsApp, Instagram, Chrome, etc... installed). If these devices/apps could: (1) Regularly track location data (2) Regularly ask users for their symptoms Then this system could allow people to know if someone they have crossed paths with has the disease or symptoms, so that they could then self isolate. I do not know anyone from these companies, but HackerNews does. Please ask them to consider this suggestion.