—Social Networks will unfold their full potential when connected people are enabled to collaborate - any time, appropriate to the current location, activity and computing environment. However, development of collaborative applications in pervasive environments is still a big challenge. In this paper we present a service-oriented approach for the development of collaborative applications on top of social networks. It consists of a conceptual platform providing a set of generic services for real-time collaboration and the integration of existing social networks. In an experimental evaluation we implemented the conceptual platform for Android devices using the Extensible Messaging and Presence Protocol (XMPP) family together with a set of reusable services for Facebook integration, user location and proximity detection, media sharing, and collaborative editing. We developed several case study applications by composing generic collaboration services to demonstrate the feasibility and val...