The only S60 certified by Skype was made by another company called iSkoot. And Skype annouces it as theirs on the 3 SkypePhones. The problem with iSkoot is that it does not use Wi-Fi, only GPRS/EDGE. So you need a data plan. If you are offline and someone calls you the call would be routed via the cellular network and you get charged. If you are in an uncovered country you get charged an International call. It's Voice over Cellular.