Project Summary/Abstract Prediabetes and obesity are major public health issues that disproportionately affect racial/ethnic minorities and low-income individuals in the United States (US). Approximately 84 million American adults have prediabetes. The recent increased prevalence of prediabetes is caused largely by the global epidemic of obesity. In the U.S, the prevalence of obesity was recently reported at about 40% adults. With the growing prevalence of obesity in the U.S., prediabetes is expected to become an even greater public health challenge. The Diabetes Prevention Program trial and other large trials have shown that a moderate amount of weight loss achieved by reducing total caloric intake and increasing physical activity can prevent or delay the onset of type 2 diabetes. However, these prevention programs involving in-person counseling can be expensive to implement and sustain in clinical or community settings over extended periods of time. The rapid rise of sophisticated digital devices (i.e., mobile applications, wireless activity trackers, social network) provides an opportunity to transform the way health care team deliver a diabetes prevention and weight loss program. These digital technologies are inexpensive and widely available and can reach large numbers of adults with prediabetes and obesity. However, despite their popularity and availability, the vast majority of individuals will stop using them within weeks because of lack of systematic behavior change approach (i.e. setting personalized short-term and long-term goals).Therefore, an urgent need exists in successfully incorporating these inexpensive digital devices into a diabetes prevention and weight loss program and sustain its effect over time. The goal of this project is to assess the effect and sustainability of a digitally-based diabetes prevention program in English or Spanish speaking adults with prediabetes and obesity. The primary outcomes are change in percent body weight and HbA1c from baseline, 5, and 12 months. In this proposed 12-month randomized controlled trial, we will randomize 255 participants into one of 3 groups with a 1:1:1 ratio: 1) a Control (usual care), 2) a Regular intervention group, and 3) a Plus group. While both the Regular and Plus group will receive a 5-month diabetes prevention intervention in an identical fashion, only the Plus group will receive a 7-month maintenance intervention. The Control group will receive an American Diabetes Association lifestyle brochure and wear an activity tracker, but no intervention will be provided. Our research team seeks to shift the current paradigm, by moving to the use of commonly used digital technology for diabetes prevention and weight loss programs, and test its sustainability. We believe that the findings from this RCT will provide new insights into how to design interventions as well as other lifestyle interventions.