iCAP: interactive prototyping of context-aware applications

Although numerous context-aware applications have been developed and there have been technological advances for acquiring contextual information, it is still difficult to develop and prototype interesting context-aware applications. This is largely due to the lack of programming support available to both programmers and end-users. This lack of support closes off the context-aware application design space to a larger group of users. We present iCAP, a system that allows end-users to visually design a wide variety of context-aware applications, including those based on if-then rules, temporal and spatial relationships and environment personalization. iCAP allows users to quickly prototype and test their applications without writing any code. We describe the study we conducted to understand end-users' mental models of context-aware applications, how this impacted the design of our system and several applications that demonstrate iCAP's richness and ease of use. We also describe a user study performed with 20 end-users, who were able to use iCAP to specify every application that they envisioned, illustrating iCAP's expressiveness and usability.