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.

The Research app requires that users install a custom root certificate, which gives Facebook the ability to see users’ private messages, emails, web searches, and browsing activity. It also asks users to take screenshots of their Amazon order history and send it back to Facebook.

Facebook did not immediately respond to a request for comment.

The program appears to violate Apple’s policies for developers using enterprise certificates to grant root access to iPhones. The certificates, which are intended to grant employers access to employees’ work devices, are prohibited from being installed on customers’ phones. TechCrunch reported that a Facebook spokesperson said the program did not violate Apple’s policies but could not explain how.

Facebook took steps to hide its involvement in the project until just before it installed the app, TechCrunch reported. Beta-testing services Applause, BetaBound and, uTest all provide services related to the research program:

Facebook began distributing the Research VPN app in 2016. It has been referred to as Project Atlas since at least mid-2018, around when backlash to Onavo Protect magnified and Apple instituted its new rules that prohibited Onavo. Facebook didn’t want to stop collecting data on people’s phone usage and so the Research program continued, in disregard for Apple banning Onavo Protect. Ads (shown below) for the program run by uTest on Instagram and Snapchat sought teens 13-17 years old for a “paid social media research study.” The sign-up page for the Facebook Research program administered by Applause doesn’t mention Facebook, but seeks users “Age: 13-35 (parental consent required for ages 13-17).”

If Apple decides that Facebook Research violates its policies, the company could move to block its use of enterprise certificates, heightening the already high tensions between the companies. In the meantime, we’ve learned about one more way Facebook is hoovering up the most intimate details of our lives, for $20 a month.