Mobile technologies targeting both eating and physical activity behavior provide new opportunities for weight management, but for data on eating behavior these rely on self-report. This results in unreliable information and is burdensome for the user. SPLENDID, an EU project, aims to take the next step in the development of these mobile technologies and is currently developing a wearable personal coach; i.e. a system that will actively monitor eating and physical activity behavior and provides real-time feedback. For the system to be implemented successfully it is essential that it is accepted by consumers and health professionals. While still under development it was investigated how the system is perceived by them. The system was discussed in a focus group with five females (age: 19–24 years) interested in weight management. Nineteen overweight young adults completed a questionnaire on their experiences with the system after 5 hours of using and wearing the system. Furthermore, twelve health professionals were interviewed on the system. Overall the system was perceived as very promising. The objective measurements of both eating and physical activity behavior, and real-time feedback were especially appreciated. However, it was emphasized that the system should be discrete, user-friendly and comfortable for the consumer, and saves the health professional time. These results of the focus group, interviews and questionnaire on user experience are promising and are being taken into account in the further development of the system.