A context-aware reminder framework, which aims to assist elderly people to live safely and independently within their own home, is described. It combines multiple contexts extracted from different modules such as activity monitoring, location detection, and predefined routine to monitor and analyze personal activities of daily living. Ontological modeling and reasoning techniques are used to integrate various heterogeneous contexts, and to infer whether a fall or abnormal activity has occurred; whether the user is in unhealthy postures; and whether the user is following their predefined schedule correctly. Therefore this framework can analyse behaviour to infer user compliance to a healthy lifestyle, and supply appropriate feedback and reminder delivery. The ontological approach for context-awareness can provide both distributed context integration and advanced temporal reasoning capabilities.