An auxiliary cellular phone module assists in making a local call while a coupled master cellular phone is roaming, wherein the auxiliary cellular phone module consists of processing unit, communication interface, cellular telephony interface, user interfaces and memory. A full-fledged auxiliary cellular phone module consists of a plurality of features that includes user interfaces consisting display, full-fledged keypad, wired and/or wireless interfaces, earpiece and microphones. A simpler version may have simplified or none at all of any of the user interfaces mentioned above. A full-fledged auxiliary cellular phone module may have many additional functionalities that helps a roaming service provider to cut costs of the local calls placed while roaming, that includes audio/visual advertisements, directions as well as many other audio/visual informational data displays. Moreover, many other features that are helpful to the roaming client may also be provided within the auxiliary cellular phone module that includes local phone book facilities, prepaid credit information and other informal data displays.