Abstract: There is provided a SIM device (20) to be connected to a SIM card (10) for a communications device, the device having a bay (35) for receiving that SIM card, and the SIM card being associated with a first communications network route. The SIM device comprises a substrate (21) having first and second surfaces (23,22), the SIM card being mountable to the first surface. A first set of electrical contacts (26) are arranged on the first surface of the substrate to engage corresponding card contacts (15) on the SIM card. A second set of electrical contacts (31) are arranged on the second surface of the substrate for engagement with corresponding contacts in the bay of the communications device. A microprocessor (25) is provided on the substrate and is electrically connected to the device contacts and associated with a second communications network route.