Digital health is rapidly expanding due to surging healthcare costs, deteriorating health outcomes, and the growing prevalence and accessibility of mobile health and wearable technologies. Data from mobile and wearable technologies can be transformed into digital biomarkers that act as indicators of health outcomes and can be used to diagnose and monitor a number of chronic diseases and conditions. The process of transforming data into digital biomarkers can be computationally expensive and evaluation methodology is poorly defined. Here, we provide a collaborative, standardized online space for digital biomarker development and validation through the open source The Digital Biomarker Discovery Project (DBDP.org). From accessing and preprocessing sensor data to development of statistical modeling, machine learning, and deep learning algorithms, the DBDP provides tools for each step of the digital biomarker discovery process. We envision the DBDP becoming a standard for the digital biomarker community and an epicenter of collaboration and exploration.