An app that tracks where you have been and who you have crossed paths with—and then shares this personal data with other users in a privacy-preserving way—could help curb the spread of COVID-19, says Ramesh Raskar at the MIT Media Lab, who leads the team behind it. Called Private Kit: Safe Paths, the free and open-source app was developed by people at MIT and Harvard, as well as software engineers at companies such as Facebook and Uber, who worked on it in their free time.
