This paper presents the design, implementation and the overall lifecycle of a software system that includes mobile and web components and that evolved having the following aspects in mind: (1) System Requirements and Architectural Design, (2) System Implementation and Deployment, and (3) System Assessment and Usability Testing. During the three years of development efforts three software prototypes were implemented utilizing service-oriented approaches. These efforts have been tested with more than 200 users during this period. The outcomes of these activities led to the design and implementation of a system architecture that relies on service- oriented approaches and open standards. Moreover, extensive prototyping with incremental development stages helped to find the balance between the design and implementation of the system while reflecting to rapid changes of software and web- based technologies. Finally, user testing for assessment and testing of the software system were employed in order to cope with the dynamic user requirements. The main outcomes of the efforts described in this paper are presented and summarized in the form of Architectural Concepts that pave the way towards an open, extensible architecture.