Moonga is a successful online mobile game developed by EverdreamSoft SA. For staying competitive in the market, Moonga needs to introduce new functionalities. For this EverdreamSoft wants to integrate Geolocalization of cards in the game. The main issue in the introduction of geo-localization, and which is the target of the Geosop project, is the evaluation of the trustworthiness of the position returned by a smartphone user and tools required for defining and managing complex geographical areas delimiting the card availability in space.