Environeo is a citizen application allowing you to report environmental nuisances that are recognizable visually, by their smell, their color or through the impacts observed by each person. The application provides information on pollution observed in water, air, or soil, and likely to cause damage to natural environments or human health. The data collected is intended for the collaborative production of environmental knowledge in a citizen science logic. They feed the work of a network of environmental sentinels supported by the SAMU environment association, which may be required to supplement this data with analyzes carried out in the field.