The use of mobile devices and their use for Internet access, for georeferentiation and services consumption had a huge increase. Today, these devices ability to establish cooperation networks and to interact intelligently and cooperatively with the surrounding environment has growing importance. In this paper, we propose a system, based on a model which uses the social paradigms in mobile ubiquitous interactions, capable to effectively connect and integrate these devices in order to improve the accessibility in the cities. The model is inspired in concepts from the theory of organizations and sociology, as the notions of "social role", "ownership" and "responsibility", to be incorporated in each device. We present an example for applying the model in the context of accessibility in smart cities for the pedestrian traffic light automatic management.