At present, elderly people are suffering from dementia and Alzheimer's disease across the world. The aged population has been increasing and continues in the coming decades. Those elderly who are suffering from dementia and Alzheimer's disease require continuous attention. Therefore, these people need a responsible person (either a nurse or a family caretaker) to look after and provide support in any case of emergency. The number of these patients is dramatically increasing. This is difficult to care for them all by hiring a personal caretaker for each patient. Consequently, with the help of electronics and computer technology, scientists currently develop efficient and user-friendly devices that can help look after a patient easily or even remotely. Hence, it is possible to look after not only a single patient but also monitor a number of patients at the same time.