Obesity is the most common diseases in the United States - an estimated 35% of adults are obese. Among kidney (KT) and liver transplant (LT) recipients, weight gain and obesity is associated with poor graft function. Yet, within a year of transplantation, habituation to a sedentary lifestyle, changes in metabolism, and immunosuppression drugs contribute to an average 4-10 kg weight gain for recipients. Recent innovations in wearable device technology can passively monitor an individual's physical activity. Additionally, incentives and health questions designed using insights from behavioral economics have been shown to motivate device engagement and improvements in health behaviors. A remotely-monitored exercise program could improve behavior change and potentially be durable because it takes advantage of the high motivation for improving health in this population. The objective of this study is to use a randomized, controlled trial to test the efficacy of a home-based exercise program using wearable devices, health engagement questions and financial incentives. Participants in the intervention arm will establish a baseline step count during the first two weeks, followed by a 12-week intervention period and a 4-week follow-up period.