(AP) -- Vonage, a pioneer of home phone service over the Internet, has a new application for the iPhone and Android phones that provides free calls between Facebook users.
The application is another step in the industrywide move away from today's phone system and its numbers and toward Internet calling.
Vonage Mobile for Facebook is available as a free download for iPhone, iPod Touch and Android phone users. They sign in with their Facebook username and see a list of Facebook friends who also have the app. Tapping a name places a call to the friend, whose phone rings. The app doesn't need to be running on the friend's phone for the call to go through.
"Essentially, we've given Facebook a voice," said Marc Lefar, the CEO of Vonage Holdings Corp., which is based in Holmdel, N.J.
The calling works over cellular broadband, so-called 3G, and over Wi-Fi. It doesn't use calling minutes, but will use up data, which could be a concern for subscribers to AT&T's new limited data plans for smart phones.
In tests between a few phones in New York, call quality varied. On an iPhone 3GS, audio delays made the calls impracticable.
The app doesn't carry any advertising. Lefar said Vonage may later charge for the ability to call landlines and send text messages. Versions for BlackBerry phones and for Windows and Mac computers are coming, he said.
There have been other applications that unite Facebook with Internet calling. For instance, another voice-over-Internet company, 8x8 Inc., provides a "call me" button that Facebook users can put on their profile page. When the button is clicked in a Web browser, calls are placed to the page's owner and the clicker. If both pick up, 8x8 connects the calls to each other.
Phone companies have been slow to adopt the possibilities and savings offered by Internet calling technology, Lefar said.
Apple Inc. and AT&T Inc. used to block 3G calling apps from the iPhone, but relented in January after the Federal Communications Commission started looking into the matter.
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