This paper presents a novel approach to assist a group of users to access and control personalized context based services by means of natural interactions. The group creation and the service activation are both based on the use of RFID tags. Each user can join a group by placing her personal tag on an RFID reader. Once the group has been created each available service, e.g. pictures slideshow, media player, recommender, can be activated and deactivated in various comfortable modes, such as through `service' RFID tags or acting on a smart object. User preferences and context, along with the service catalog, are stored in a Context Aware Platform. The platform fuses the preferences and the contexts of the group members to custom tailor the services to the group's dynamic profile.