Mobile devices and services are gaining every day more and more users with new services and applications appearing every day. The high success of new powerful mobile hardware able to support innovative services, like the iPhone and its competitors Blackberry and HTC, has shown that the users are anxiously waiting and are ready to adopt new (mobile) services and applications. Today mobile services are more complementary of the fixed network services, allowing the users to access traditional fixed network based services, while being mobile. However now that the users have been accustomed in mobile services and content access and in response to their needs, new services and new challenges start appearing that do not have an equivalent fixed wire service, ranging from location based trust services to middleware for network handover. In addition mobile users are recreating the very successful operation of internet, where services are based on a collaborative model for the creation and exchange of (mobile) content. The main research effort of our group is based on the vision of the future needs of collaborative mobile services. In this report we present 10 papers and one position paper, representing the main work areas of the group. Our work is mostly based on the notion of virtual tags as the basic collaboration unit of mobile users.