iPhone免费电话软件Viber

最近出现的Viber，非常受欢迎，抢占了Skype的市场份额，关键就在于它的免费。iPhone之间，无论在哪里，只要能使用3G或者WiFi，就OK了。Android版本也即将面世。

http://www.viber.com/

• 
  International free calls to other Viber users using
  3G or Wi-Fi.
  
• Check your contacts, you can see which of your iPhone
  contacts is already on Viber.
• Go ahead and call. It's free* and it works great!
  * Calls use your data plan