First time doing one of these posts. :3
TLDR: Facebook will once again begin paying people to monitor how they use their phone through a new app called Study. The app will monitor which apps are installed on a person’s phone, the time spent using those apps, the country you’re in, and additional app data that could reveal specific features you’re using, among other things.
Not 100% sure the legitimacy of the verge, but here's the sauce; https://www.theverge.com/2019/6/11/18661595/facebook-study-app-monitor-phone-usage-pay