In Spring 2017 (1st cycle), 216 adult citizen scientists (≥18 years) were recruited in person, and online, through a combination of convenience sampling and self-selection. Citizen scientists installed the Ethica application on their personal Android or iPhone device for 8 consecutive days to provide a complex series of objective and subjective data. They answered a succession of validated surveys that were pilot-tested to assign different smartphone triggering mechanisms (e.g. user-triggered, scheduled-triggered) to maximize compliance. The validated surveys captured physical activity (IPAQ), sedentary behavior (Adapted PACE survey), motivation (PALMS), the perception of the outdoor and indoor environment (Adapted NEWS), and eudaimonic well-being (QEWB). Ecological momentary assessments were employed on each day to capture not only physical activity but also physical and social contexts along with barriers and facilitators of physical activity, as relayed by citizen scientists using geo-coded pictures and audio files. To obtain a comprehensive objective picture of participant GPS-based location data, motion-based activity, and interaction with smartphone was also surveilled for 8 days.