Over a 10 week period, participants were asked to report any gastrointestinal symptoms using Ethica. During the first 10 days, participants were also asked to take photos and answer 3 times daily surveys on recent food choices. Participants reported whether they were eating in restaurants or take-out food. The Ethica app linked participant data to location. Participants also completed an online survey either 1 or 2.5 weeks after day 5 asking them to recall their food choices for days 2 to 8. By comparing the survey with the Ethica data, the extent of recall bias was assessed. This proof of concept study also examined the feasibility of using Ethica to support the investigation of enteric illness and inform dynamic simulation models of outbreak detection. Using participants’ reported experiences with the system, the project identified hurdles to scaling up the use of Ethica to a larger, more diverse study population and to applying this technology to other questions not sufficiently answered using traditional survey techniques.