Cell phone maker Motorola already plans to launch Wi-Fi smartphones with Skype's VoIP software. These VoIP phones will provide cellular GSM service as usual, but in the surrounding of a Wi-Fi network the phone will be able to call over VoIP instead of GSM.
While some see mobile operators building VoIP into their networks, some expect them to treat VoIP mainly as a threat to mobile revenue. But Motorola, which needed a partner wireless operator to support the coming VoIP phone, reported that VoIP's potential advantages were apparent enough to cellular providers.More about VoIP at IHT