This paper proposes to create a communication system between cars to prevent and also to handle an accident. In the case of accident prevention, the system broadcast information to other cars about the condition of the surroundings by giving a warning notification upon some event, such bumpy road, speed bump and sudden brake. The system uses an Android based smart phone as the main platform. It utilizes the phone's internal built-in sensors for the event detection and localization and employs Wi-Fi Direct for the fast and cheap inter-cars communication to other Android devices in the surrounding areas. In the case of accident handling, the system implements an automatic emergency request by sending an emergency related data to dedicated numbers when the car is involved in an accident. The overall system has been tested for above sample situation in a real car on the roads and it proved to be very responsive and readily deployable with no additional hardware. Acquired sensor data are displayed on a map in the receiving Android Smartphone. The communication system between cars can lead to useful applications that help promote safety. By incorporating the information from the system's peers, the peers can cooperate together to prepare for any unwanted incident.