In this paper, a digital assistant system was designed and implemented to help the patients of early
dementia, their families and their caregivers. Traditional digital assistant systems are mainly patient-oriented
ones which mainly focus on patient status monitoring, patient emergency identification, and peripheral
control using IoT technology. On the other hand, the system proposed in this paper focused on maintaining the relationship between the patient and the people around him/her by using social network service
technology to minimize the social disruption of the patient. It also provides recall therapy, light therapy,
cognitive training, which are known to be helpful in relieving the progression of dementia during daily life.
Considering that the patients with early dementia are not familiar with the operation of digital information
equipment, we added voice and video interfaces in addition to the screen touch interface so that patients
can use the service easily. The system implemented in this paper is designed as an open architecture, so it
is easy to add new services.