Remember when everyone was upset because Facebook forced us to download the Messenger app on our phones? Well, Mark Zuckerberg's social network doesn't think there's such a thing as too many Facebook apps. In fact, they want you to make calls with one of them. That's right: Facebook has been testing a standalone phone app for Android, although it's not clear what for.

Although Facebook tests a lot of things that end up being binned, the company has toyed with the whole make-a-call thing for a while now. After acquiring WhatsApp last year, they announced that the mobile messaging app would be getting Voice over IP calling features.

Its Messenger App got VoIP in 2014 in the United States. Now, Android Police snagged a screenshot showing an Android device with the new Facebook app, called simply "Phone".

"Phone is a new app that shows you info about who's calling and automatically blocks calls from commonly blocked numbers", the test shows. Android Police says it might be just a dialer replacement, which doesn't seem very appealing to consumers.

Facebook did confirm to Mashable that they are "always testing things", but didn't explain what this is all about. Maybe because there's a big event coming for the company: the F8, or Facebook Developer Conference, is scheduled for Wednesday and Thursday in San Francisco, and major updates to the Messenger app are expected.

In April of last year, Facebook forced its users to download a standalone app for the chat feature of the social network, a move that infuriated a lot of people but ended up working out well; the Messenger app quickly shot to the top of most downloaded free apps for iOS and Android.

More recently, they announced the Messenger app will allow users to send and receive money

Now, TechCrunch reports that Zuckerberg plans to open up the Messenger app as a platform, in which third parties can integrate their messaging capabilities.

An analyst also predicts both Facebook and Messenger will get a speech-to-text feature, that should make its way to Facebook-owned WhatsApp at the same time.

Mobility has become key to Facebook's earning, as more than half of ad revenues come from the mobile app and not the desktop version; securing fundamental real estate on your phone is essential for the company's growth. More to come in the next few days.