The concept of One Health, a system-based approach that acknowledges the interdependence of human, animal, and ecosystem health, has grown in prominence over the past few decades. This transdisciplinary concept is increasingly important as the climate crisis, directly and indirectly, impacts all aspects of the planetary web of life. In tandem with the rise of One Health has been the increasing adoption of digital technologies into healthcare practice and within methods used to research human and environmental health. Emerging at the intersection of One Health and Digital Health is the idea of One Digital Health. This syncretic concept explores the opportunities that digital health presents to further the utility and operationalisation of One Health. A notable feature of the One Digital Health model is the role of citizen engagement. This feature aligns the digital approach with many One Health interventions that use citizen science to improve human, animal, and environmental health. This paper reports the results of a rapid review followed by a deep-dive into several representative studies exploring the intersections of One Health, digital health, and citizen science to identify new domains of innovative practice that supports resilience in the face of climate change and environmental health hazards. A focus on air quality reflects its importance in the One Health literature.