Japan has problems with the declining birth rate and growing of aging population. The number of solitary aged persons has been on the increase. In social situation like this, a solitary death of aged person becomes a serious problem and to establish the system to prevent it is urgent necessity. Some safety equipments for aged people are already sold in Japan, but they have not been widely used because most of them are considerably expensive and users need to pay contract price or usage fee. By taking into consideration an increase in solitary aged persons toward an aged person society, we studied and developed the application, “Anshin”, for mobile devices to prevent solitary death and the network system, “Otassha Tushin”, to monitor and support conditions of solitary aged persons on a server. We will distribute these systems for solitary aged persons and their family or caregivers for free.