The digital ecosystem for tobacco, alcohol and unhealthy food marketing is complex and is changing quickly. Understanding the digital ecosystem is essential to being able to make decisions and advise policy-makers on what is needed to ensure that children are safe and not exposed to marketing of unhealthy foods – those high in fats, sugars and/or salt – which the evidence shows has a strong impact on children’s eating behaviour. WHO has a key role to play in monitoring, measuring, educating and informing the policy debate on regulation and control of the digital media ecosystem. This paper summarizes recent changes in the digital ecosystem in detail, explains which factors and stakeholders are driving these changes and sets out the consequences for food digital marketing of these ongoing changes.