The Ministry of Health, Labor and Welfare has developed a new coronavirus contact confirmation application (COCOA)  to help prevent the spread of new coronavirus infections. This application uses the smartphone's proximity communication function (Bluetooth), with the consent of the user himself, to ensure privacy so that they do not know each other. The user will receive the notification that they have come into contact with a person who is positive for the new coronavirus infection.

By knowing the possibility of contact with a positive person, the user can quickly get support from the public health center, such as taking an examination. It is expected that the increase in the number of users will help prevent the spread of infection.