Objectives and Significance. Smartphones have the capability to monitor health-related behaviors (exercise, diet, etc.) and provide social support which has the potential to play a powerful role in health promotion. The objective of this study is to refine and pilot test the Social POD app for personalized health monitoring and interaction founded on a combination of social networks, recommender systems, motivational research, and health behavior theory. Currently, we are recruiting for usability testing among obese and overweight (BMI >25 kg/m2) adults (n=20) with our basic Social POD app. Our proposed project, which seeks to supplement our current line of research investigating mHealth interventions for overweight and obese adults, has two aims: