Japanese telecom KDDI announced that it will start sales of a mobile phone-based car navigation service in Japan on September 8. The service will be available on fourteen phone models and will cost 315 Yen a month or 157 Yen for one day. KDDI will market the service for passengers, as it is forbidden for drivers to use mobile phones in Japan. It offers all the basic functions of regular car navigation systems, including relevant navigation maps, voice guidance, the latest traffic reports, selections of the fastest available route, and car park information.