Concerned with setting strategical perspectives in the Mauritanian capital, the Urban Community of Nouakchott (UCN) has engaged with a pondering on tools for urban planning and managing from 2030 onwards. This pondering leads to the elaboration of a new Planning and Urbanism Blueprint (SDAU). This Blueprint replaces that of 2003, which was meant to serve as a reference. For this matter, a collaborative online platform has been set. From a smartphone or a computer, users can freely give their opinion about maps on opendata. The three main contributions are: the identification of issues in the city, the identification of positive points that are to be kept and the different ideas and free propositions.