With integration of Google Voice and Gmail , which essentially allows users to place voice calls via Gmail to phones anywhere in the world. Calls to both landlines and mobile phones within the U.S. are free;
Google charges a small fee to dial numbers in other parts of the world, depending on the region and whether it's a landline or a cell phone.
users with Google Voice can take advantage of Google voice features within the Gmail context, such as the ability to record phone calls, listen to users leaving a voice mail and then join a call, or have incoming calls "ring" both a separate phone as well as the browser.
Software Usage
Download a small client (for either Windows, the Macintosh, or Linux) which will add the option of software-based echo cancellation and other magic, using technology developed by Global IP Solutions and Vidyo, as well as Google itself.
Price : Call is free for US and Canada , For other country Check it here
Price : Call is free for US and Canada , For other country Check it here
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