On Thursday, the company added the free calling functionality for U.S. users of Facebook Messenger for Android -- and Facebook Home, which runs Messenger, by association. The rollout will take place throughout the day and does not require an application update, a company spokesperson told CNET.
The addition introduces a "Free Call" button accessible from a Facebook buddy's contact page. Those with Facebook Home also can initiate calls from Chat Heads, although it requires several clicks to do so: Click the three dots next to your contact's name, select "Open in Messenger," and then navigate to the person's contact info.
Once you finally get to the Free Call button, Facebook will dial up your friend over Wi-Fi or your phone's data connection.
The option offers people a way to make phone calls without using minutes from their smartphone's voice plan, which makes the social network a potential threat to carriers.