TFW is not shown on every iPhone. Only iPhones that use SIM cards from TracFone Wireless or its brands (like Straight Talk or Total Wireless) will have the TFW carrier appear. When your iPhone directly carries the SIM of any of the major carriers, such as AT&T, Verizon, or T-Mobile, then it will not display TFW. So, what does TFW mean on the iPhone? It simply goes to tell you that it uses the TracFone network.