Roamcell The Travel SIM is an award winning prepaid global roaming SIM card MVNO. It is a tailored network to allow frequent travelers to save upto 70% in roaming. NO BILLS, as it is PREPAID. Clients can make and recieve calls in 220 countries worldwide, at a fraction of the cost they would incur with their normal operator’s prices. Incoming calls are FREE to receive in over 90 countries and outbound calls start from as low as $0.42/min.