https://www.theverge.com/2019/1/29/18202880/facebook-research-enterprise-root-certificate-onavo-techcrunch

Facebook has run a program to collect intimate user data from paid volunteers for the past three years, according to a new report. TechCrunch reported that the company has been paying people ages 13 to 25 as much as $20 month in exchange for installing an app called Facebook Research on iOS or Android, which monitors their phone and web activity and sends it back to Facebook. The company confirmed the existence of the research program to TechCrunch.

Facebook was previously collecting some of this data through Onavo Protect, a VPN service that it acquired in 2013. The data has proven extremely valuable to Facebook in identifying up-and-coming competitors, then acquiring or cloning them. Facebook removed the app from the App Store last summer after Apple complained that it violated the App Store’s guidelines on data collection.