Skype has announced an updated version of its iPhone application that allows users to make calls over 3G networks.
The Skype 2.0 application for the iPhone will let customers make and receive free Skype-to-Skype calls for a trial period until the end of this year.
Users will be able to call mobiles and landlines around the world at low rates, which Skype will announce in the coming months.
"Using Skype on iPhone without being restricted to the availability of a Wi-Fi network will open up new ways for Skype customers to stay connected and make free or low-cost calls whenever they want, wherever they are in the world, " said Skype mobile general manager Russ Shaw.
"This new version is a great step towards enabling our customers to take and use Skype everywhere they go."
The application is available from the App Store and is compatible with the iPhone, iPhone 3G, iPhone 3GS, iPod touch and the iPad. Skype requires the iPhone operating system version 3.0 or above.
Skype said in a blog post in February that it was delaying the addition of 3G capabilities to its iPhone application so it could provide users with the "very best audio quality" .
The firm said that Skype 2.0 has near CD-quality for Skype-to-Skype calls using wideband audio on the iPhone 3GS or the second-generation iPod touch.
The application also boasts improved start-up time and an enhanced call quality indicator, which Skype said helps customers choose the best moment to make calls.
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