Moreover, the technology related to recognition of human physical activities, health condition and medical status can be used to recognize context for enhancing HCI. UCHS and reminder system are two examples that use vital signs of people to provide appropriate service to the elderly people accordingly by improving functionality of applications. The intellectual disaster alerts system provides alerts in mobile devices in case of expectation for disaster happening by using context information in order to increase the richness of interaction and communication in HCI. While in iMuse system this richness is covered by providing exhibit information to the museum’s visitor in a usable and flexible manner on their own mobiles. All aforementioned applications attempt to improve implicit access to the context information in order to enhance interaction between application and human to provide more efficient and useful computational services.