Facebook doesn’t just want you to poke, message and stalk your friends. Now it wants you to actually talk to them.

The company this week started rolling out a free calling feature in its Messenger app for iPhone users in the United States. Inside the app, you can choose a friend, tap the “i” button in the top-right corner and select “Free Call.” If your friend also has the Messenger app, the call should go through.

But will anyone use it In the past, the idea of free voice minutes might have sounded like a blessing. But today, many new phone plans offered by carriers â€" like Verizon Wireless and Sprint â€" already include unlimited voice minutes. Calling someone with a cellphone the normal way is more straightforward than doing it through an app. Also, call quality for Internet-powered voice calls is often poor, said Jan Dawson, a mobile analyst at Ovum.

So where might Facebook calling actually have an impact For teenagers who spend most of their tim on Facebook, the Messenger app could be a convenient way to quickly switch from a Facebook chat to a phone call, Mr. Dawson said. And if and when Facebook introduces the feature to international calling, it might be convenient for business travelers or people with families overseas â€" although many of those types of users are probably already on services like Skype, Mr. Dawson said.