Chatbots and COVID-19: Taking Stock of the Lessons Learned.

While digital innovation in health was already rapidly evolving, the COVID-19 pandemic has accelerated the generation of digital technology tools, such as chatbots, to help increase access to crucial health information and services to those who were cut off or had limited contact with health services. This theme issue titled "Chatbots and COVID-19" presents articles from researchers and practitioners across the globe, describing the development, implementation, and evaluation of chatbots designed to address a wide range of health concerns and services. In this editorial, we present some of the key challenges and lessons learned arising from the content of this theme issue. Most notably, we note that a stronger evidence base is needed to ensure that chatbots and other digital tools are developed to best serve the needs of population health.