This project proposes to use mobile devices to develop new tools for pediatric obesity prevention and treatment targeting underserved minority adolescent populations at high risk for obesity and related diseases. We will use off the shelf, validated and wearable wireless sensors to measure physical activity, blood pressure, sleep, heart rate, galvanic skin response and blood glucose levels and communicate the measured information to a mobile phone using a wireless interface. This will deliver a record of behavior and health data that is time-stamped, synchronized, and geographically localized using GPS to a secure server. Data will then be analyzed and displayed to participating health professionals to provide them with readily interpretable records of continuously monitored energy expenditure, recorded and synchronized with other essential biological, behavioral and geographical data. To accomplish this project, 50 African American and Hispanic youth (50% female, ages 12-17) will be recruited into the research in advisory capacities, to test the sensors during development, and to wear the sensors for three non-contiguous weeks. To test the sensors prior to use with minority youth, 30 college students age 18 and above will be recruited to try out the sensors in and outside of the laboratory in order to make sure that all sensors are in perfect working order before testing them in minority youth populations. An advisory group of medical professionals will be assembled to guide us through the process of developing a web interface that will ensure that the right information will be displayed in an easily interpretable fashion. The advisory group will participate in regular meetings to develop and test the web interface. Using the data acquired, health professionals will be able to visualize average amounts of physical activity, sleep, sedentary behaviors (daily or weekly) as well as daily patterns. Average blood glucose, heart rate, and stress levels (daily or weekly) as well as daily patterns will also be available. Practitioners will be able to see when and where activity and metabolic events are occurring, enabling preemptive and preventive strategies as well as targeted interventions to prevent and treat pediatric obesity in underserved and at-risk minority youth.