Facebook, a company that makes billions of dollars by keeping us all mindlessly addicted to its social apps, has a clever way of figuring out what to build next. The social networking giant reportedly has an internal system that tracks the success of up-and-coming apps to help it decide which ideas to copy from smaller startups and other companies, according to a recent report in the Wall Street Journal. This “early bird” warning system reportedly utilizes mobile usage analytics technology from Onavo, an Israeli startup Facebook acquired in 2013. Onavo’s app uses a technique that routes people’s mobile usage through a third party server for privacy purposes, but it also “gives Facebook an unusually detailed look at what users collectively do on their phones,” according to the report.