Use Facebook? Own an iPhone? Call Your Facebook-Using, iPhone-Owning Friends for Free

iTunes Facebook's Messenger app for iOS.

If you find yourself perpetually blowing through the minutes on your cell phone plan and you spend a lot of time talking to people you’re also friends with on Facebook and those same people happen to own iPhones and they’ve got the Facebook Messenger app installed, there’s a solution.

Facebook has rolled out free voice calling to other Facebook users via its Messenger app for iOS. Both you and your friend will need to have the app installed for this to work, of course, but assuming that’s been taken care of, you’ll be able to make calls to one another using your phone’s cellular data connection or an available Wi-Fi connection (this should work over Wi-Fi for iPad and iPod Touch owners, too). It’s not technically free if you’re paying for your data plan or broadband connection, but none of your voice minutes will be used in the process. BuzzFeed has a simple step-by-step guide here that details how the calls are initiated.

This is not a new trick, mind you. Several other VoIP (voice over internet protocol) services – Skype being the most well-known – can do the same thing, but across platforms (Apple, Android and others) and between different devices. But Facebook has a lot of users, many of whom already use Messenger. And it’s unlikely this feature wouldn’t be rolled out to non-Apple devices sometime in the not too distant future.

The free calling feature has reportedly been available to users in Canada for a while and is now beginning to roll out to users in the U.S. as well.

Facebook launches free calling for all iPhone users in the US [The Verge]

Aamoth handles news, reviews, how-to's and videos as TIME's technology editor. He lives in Boston and has spent more than 15 years in the tech industry.