Updated

Calling all iPhone-based Facebook users. Today, the social network launched a feature within its Messenger app that gives iPhone owners the ability to call each other while connected either via Wi-Fi or your wireless provider's data network. This will no doubt compel millions of Americans to engage in a "can you hear me now?" marathon in the coming days.

It's simple to connect. To place a call, begin a conversation with someone in Messenger, then press the "i" button in the top right hand corner of the screen. Next, tap "Free Call" towards the middle of the screen.

When we attempted to use the feature, the button was grayed out on one end and absent on the other, even though both users had up-to-date versions of the Facebook Messenger apps installed. We're guessing the service is still being rolled out.

If this feature proves to be consistently stable and functional, Skype could have a real competitor on its hands, not to mention Google Voice. Wireless subscribers who aren't already signed up for an unlimited plan would also have the flexibility to opt for less voice minutes, knowing that more of their calls will be carried over data pipes.

However, before any of that happens, the free calling feature needs to pass usability and call quality tests. Stay tuned for continuing coverage of this story, which will include hands-on testing and impressions once the service is completely up and running.

via The Verge, Buzzfeed