The information overload resulting from the growth of the Internet increases the need for efficient mechanisms to identify and manage information relevant for users and groups of users within web-based interactive applications. As users can be grouped according to shared interests, characteristics and interactions, groups form convenient structures to support the required personalization.Previous work on the subject of implicit groups, carried out in areas such as computer networks and social media, suggests its usefulness in the development of web-based applications, specially in the way content is shared and user personalization is achieved. In this paper we investigate the dynamic identification of such groups based on the generation of extended user profiles and the application of content-analysis features, provided by an external framework. Our approach extends common explicit user profiles with implicit extracted data reflecting each user interests and interactions with other users and with the system.In order to draw conclusions about the use of implicit groups as building blocks for web applications, we present a tool that allows an easy integration of the concept in web applications. Finally we specify an application scenario and discuss the tool integration into the Moodle platform.

In this paper we discuss how the concept of implicit groups is used to build and manage extended user profiles enabling an easier way to supply personalized features and/or information, and guide their dynamic updating. This approach extends the individual user profiles, which are explicitly defined by the user in typical interactive applications and environments, with additional information that reflects the interests, characteristics, and interaction patterns shared among users. Such extended data is implicitly and automatically obtained through the analysis of the user behavior and the corresponding interactions with the system and other users.We developed a tool (TIG) that enables the dynamic discovery and management of new groups based on the generation of extended user profiles in interactive applications or environments. The main goal of the tool is to support the integration of the above concept and its associated functionalities into existing or newly developed interactive applications. We discuss how the tool enables the integration of implicit groups into an existing collaborative environment (Moodle), as a way to provide extended functionalities for sharing information according to the extended user profile. We discuss this extended Moodle functionality and its use in a college campus application to spread information among students and teachers.