In Japan, when an accident occurs on a highway, the driver is required to move the vehicle 50 m behind the stopped vehicle and put a warning triangle and a warning flare. However, about 4,700 secondary accidents by following vehicles have occurred annually. In order to clarify the problem of the evacuation procedure, we conducted experiments to measure the working time of the process evacuating outside of the stopped vehicle. The recorded average time was 88.5 s, and only 40% of subjects completed all the steps. After the experiment, in the interview the majority opinion was that “It is difficult to grasp the accurate position of 50 m behind the stopped vehicle”. From examining the findings, this is one of the causes of the secondary accident. Therefore we conducted the other experiment to measure the error between the point expected to walk 50 m and the actual distance. Less than 30% of the subjects could walk within 3 m of the error. From examining the experiments, the drivers who do not know the evacuation procedure and have no experience using the warning triangle and the warning flare need support to accomplish the evacuation procedure in a short time without mistakes. Therefore we designed the smartphone application that is able to support the evacuation procedure. The drivers can use it from just after they get out of the accident vehicle and inform the following vehicle of the existence of the stopping vehicle, to their safety is secured.