Skype has announced the release of a new version of its iPhone app which will enable users to make and receive Skype to Skype calls and to call mobile and landlines around the world at low rates.

According to Cellphone Digest, Skype to Skype calls on 3G will be free for a trial period that supposedly will run to the end of 2010. The new version is compatible with iPhone, iPhone 3G, iPhone 3GS, iPod touch and iPad and the software requires iPhone OS version 3.0 or above.

The new application for the iPhone comes with improved sound quality for Skype to Skype calls using wideband audio on iPhone 3GS or 2nd generation iPod touch and onwards. In addition it will help users to choose the best moment to call by indicating call quality. Skype also announced improved start-up time and rapid access to dial pad from the home screen.

“Using Skype on 3G has been the number one request among our iPhone customers. This new version is a great step towards enabling our customers to take and use Skype everywhere they go”, said Russ Shaw General Manager for Mobile, Skype.

The iPhone application is available for download (for free) here.