This dual mode phone is a novel mobile communications device that combines the mobility of the GSM network with innovative IP telephony. The device hooks up to the GSM network when the user is on the move or to the Internet for VOIP via WLAN when the user is at home or at a hotspot. This means the customer is always connected to the cheapest system, receiving a single invoice and using a single voice mail system. The design is based on general T-Com design principles: clear-cut forms, high-grade materials and ease of use.