concept of relevancy is described in the following definition of context awareness: "the set of environmental states and settings that either determines an application's behavior or in which an application event occurs and is interesting to the user". Different levels of context, in terms of low and high level have also been outlined. Low-level contexts consist of time, location, network bandwidth and orientation. A high-level context consists of the user's current activity and social context.

A three-level model of context awareness