Tourism development is transforming the face and the organisation of many cities and countryside. The number of tourists increases, generating huge concentrations in some places and a spread of places visited and accommodation. Tourism is undergoing major changes because of the volume of innovations that are intended for it. Approach as a vector of development, tourism sets off many questions as to how it is redesigned and decided. The sharing economy is part of these innovations. This research focuses on the implications of the collaborative economy for tourism and destinations. While several research highlight the economic and social impacts related to the “new” accommodation, the knowledge of the distribution of overnights stays is currently falsified because national organisms fail to take into account the huge diversity of alternative accommodation. Wallonia, as case study, offers a diversity of destinations linked to the proximity of Brussels, historical cities, forest areas and gastronomy. To understand the influences of the development of “new” accommodation on host communities, a first step should to study their location and spatial expansion schemes. First, the databases relating to exchange platforms (Housetrip, AirDNA, HomeAway...) are consulted as well as official statistics of tourism. Secondly, these data are compared with the location data from mobile telephony. In accordance with the General Protection Regulations, a query was constructed to identify tourist overnights. The paper shows the first maps and reflects on the ethical use of the data for the research and of the use of ITC to circumvent the official accommodation.