Free voice calling hit the iOS app in early 2013, followed by Android more than a year later. Now users of both apps can open any Facebook Messenger group chat and press the phone icon in the upper right corner to initiate a call.
You'll be directed to a second screen, where you can manage participants—add or remove friends with a single tap. The participant limit is capped at a whopping 50 people, Facebook confirmed.
"If you have the latest version of Messenger, you should see the phone icon appear in group conversations within the next 24 hours," Messenger chief David Marcus wrote in a Facebook post. "Give it a try, and as always, let us know how we can make it even better for you."
Wednesday's announcement comes just two weeks after the instant messaging app reached a milestone 900 million monthly active users.
For now, group chat only works for voice calls. You can conduct one-on-one video chats via iOS and Android, though; just touch the camcorder symbol to start a virtual conversation. Skype, meanwhile, recently brought group video calling to mobile phones and tablets.
Earlier this month, Facebook added three new tools designed to make chatting with people—and businesses—even easier. Exchange Messenger Codes to verify the conversation you're striking up with a relative stranger is legitimate; Messenger Usernames also serve as an authentication tool. Messenger Links, meanwhile, are shortcuts for opening new lines of communication: Add your link to a social media profile to offer fans and followers a new way to reach you.