Health informatics has a major role to play in optimising the management and use of data, information and knowledge in health systems. As health systems undergo digital transformation, it is important to consider informatics approaches not only to curriculum content but also to the design of learning environments and learning activities for health professional learning and development. An example of such an informatics approach is the use of large-scale, integrated public health platforms on the Internet as part of health professional learning and development. This article describes selected examples of such platforms, with a focus on how they may influence the direction of health professional learning and development.Significance for public healthThe landscape of healthcare systems, public health systems, health research systems and professional education systems is fragmented, with many gaps and silos. More sophistication in the management of health data, information, and knowledge, based on public health informatics expertise, is needed to tackle key issues of prevention, promotion and policy-making. Platform technologies represent an emerging large-scale, highly integrated informatics approach to public health, combining the technologies of Internet, the web, the cloud, social technologies, remote sensing and/or mobile apps into an online infrastructure that can allow more synergies in work within and across these systems. Health professional curricula need updating so that the health workforce has a deep and critical understanding of the way that platform technologies are becoming the foundation of the health sector.