Carsten Schimanke of Royal Philips Electronics has confirmed that a U.S. wireless carrier will start offering voice-over-Wi-Fi service later this year, according to PC magazine. The service is based on Philip's Nexperia 6120 chipset, which features Unlicensed Mobile Access (UMA) technology. It will enable customers to use their cellphones to make calls on their home Wi-Fi networks. Schimanke refused to discuss their U.S. carrier partner, but its Nexperia 6120 chipset is built in the Samsung T709 slider phone, which was demonstrated at CES with T-Mobile branding. Besides the handset will use UMA technology to seamlessly transfer calls between the cellular network and Wi-Fi access points, and T-mobile has already confirmed its commitment to this technology. So it seems that T-Mobile will be the carrier Schimanke was referring to. The official launch date and pricing weren't revealed, but according to Philips' employee the service will be available for a few dollars a month, flat rate.
Source: PC Magazine