ComfortUp! is a citizen collaboration program which will identify the most and least comfortable places in the city regarding environmental aspects as noise and thermal conditions. All this information will be used to draw the environmental comfort map of your city and will be taken into account in the decision-making processes for the enhancement of urban spaces. You will become an environmental explorer, equipped with your mobile. You will have to overcome several challenges to get this mission completed. Shall you come with me for a walk around the city?