Facebook's Messenger App Is Tracking More Data Than You Think
 

By now we should all know that Facebook collects all your data to use as it pleases. Why? Because regardless what the company does to you, it's apparently not enough to make you stop using Facebook. In an email, Zdziarski said that Messenger is logging practically everything a user might do within the app, from what and where they tap, to how often a device is held in portrait versus landscape orientation; even time spent in the Messenger app, versus the time it spends running in the background.

http://www.hardocp.com/news/2014/09/...n_yo u_think/