The StudyU Health app is part of the StudyU platform, together with the StudyU designer. With the StudyU designer, scientists are given a web application to digitally specify, publish, and conduct N-of-1 trials. The StudyU app is a smartphone application with innovative user-centric elements for participants to partake in the published trials and assess the effects of different interventions on their health. Thereby, the StudyU platform allows clinicians and researchers worldwide to easily design and conduct digital N-of-1 trials in a safe manner. StudyU has the potential to change the landscape of personalized treatments both for patients and healthy individuals, as a free collaborative tool for researchers, and as a tool that can be integrated in clinical practice.