Skype has launched a new version of its client for Apple's iPhone that can make calls to other Skype users over a 3G network.
Skype-to-Skype calls over wi-fi will remain free, but Skype will begin charging for Skype-to-Skype calls over 3G after the end of 2010.
Users may have to pay an additional charge to their mobile operator for the 3G data traffic, according to Skype. They will also have to make sure that their data plan's terms and conditions allow IP telephony.
With the new Skype software, owners of the iPhone, iPhone 3G, iPhone 3GS and second- or third-generation iPod touch can make calls using Skype.