[en] After the Fukushima accident, initiatives emerged from the public to carry out themselves measurements of the radioactivity in the environment with various devices, among which smart-phones, and to share data and experiences through collaborative tools and social networks. The objective of the OPEN-RADIATION project is to offer to the public the opportunity to be an actor for measurements of the radioactivity in the environment using connected dosimetric applications on smart-phones. The challenge is to operate such a system on a sustainable basis in peaceful time and be useful in case of emergency. In 'peaceful situation', this project is based on a collaborative approach with the aim to get complementary data to the existing ones, to consolidate the radiation background, to generate alerts in case of problem and to provide education and training and enhanced pedagogical approaches for a clear understanding of measures for the public. In case of emergency situation, data will be available 'spontaneously' from the field in 'real time' providing an opportunity for the emergency management and the communication with the public. The practical objective is i) to develop a web site centralising data from various systems/dosimeters, providing dose maps with raw and filtered data and creating dedicated areas for specific initiatives and exchanges of data and ii) to develop a data acquisition protocol and a dosimetric application using a connected dosimeter with a Bluetooth connection. This series of slides describes the project