Until now, Apple's programs allow VoIP on iPhone just to use the wireless LAN. In the latest development version of OS for the first time they also become possible to telephone calls via UMTS. However, VoIP communications prohibits multiple data rates.

Shortly after the appearance of such a possibility, some companies have already announced that it will allow for VoIP calls via UMTS: iCall offers VoIP service acting solely in North America, and Fring integrates various services, like Skype, MSN Messenger, Google Talk, ICQ, VoIP and AOL Instant Messenger. Also circulated rumors about having to receive the Skype client running on 3G networks.

Internet discussions via UMTS may in some cases be cheaper than traditional phone calls, in addition to UMTS is available in far more places than the WLAN. Nevertheless, the company iCall notes that AT & T network in the U.S. may be too weak to handle VoIP.