Through the Data Modelling Process of Turimov, an Ontology-based Project for Mobile Intelligent Systems Juan Garc´ ıa, Francisco J. Garc´ ıa-Pe˜ nalvo and Roberto Ther´ on Abstract Functionality in terms of software can be defined as the quality of a soft- ware system of being functional, according to its specifications. Functionality tests represent a crucial aspect during the last phase of the development process of a soft- ware system. This paper describes a case study performed using OWL-VisMod, in order to evaluate its functionality, during its last phase of development. This case study describes the development of a data modelling process, for a project called Turimov, a recommendation system for mobile devices (smartphones, tablets and PDA’s), to support the tourism activities in the region of Castile and Lion Spain. Keywords Functional testing, OWL-VisMod evaluation, Ontologies Modelling 1 Introduction The International Organization for Standardization (ISO) defines the usability as the quality that let a product to be used by specific users, to reach specific goals with effectiveness, efficiency and satisfaction, in a specific context of use (ISO/IEC9241). Usability refers to the capacity of a software product to be used, especially those products that interact with people [9]. In the specific context of the Knowledge Representation Systems (KRS), the development of diverse usability tests becomes crucial, in order to detect inconsistencies, errors or other aspects that the system designers did not previously considered. The most visible aspect of this approach Juan Garc´ ıa, e-mail: ganajuan@usal.es, Computer Science Department, University of Salamanca, Spain Francisco J. Garc´ ıa-Pe˜ nalvo, e-mail: fgarcia@usal.es Computer Science Department. Science Education Research Institute (IUCE). GRIAL Research Group. University of Salamanca, Spain Roberto Ther ´ on, e-mail: theron@usal.es Computer Science Department, University of Salamanca, Spain 1