The purpose of this Notice of Special Interest (NOSI) is to encourage grant applications to support the evaluation of the utility and validity of digital health and artificial intelligence (AI) tools and technologies in epidemiological, clinical, and intervention research. The intent is to support the addition of new measurement modalities to evaluate existing and recently developed but not yet validated digital health and AI tools such as sensor technologies, smartphone applications, software as a medical device (SaMD), and AI algorithms.