Accessible internet betting and casino apps on phones are contributing to a surge in problem gambling and potential addiction among hundreds of millions of people worldwide, as the industry is now said to be on track to be worth $700 billion by 2028.

“Gambling harms are far more substantial than previously understood, exacerbated by rapid global expansion and digital transformation of the gambling industry,” say the members of a commission on gambling set up by The Lancet, a UK-based medical publisher.

Some of the effects of gambling addiction are well known, such as the impact on finances, employment, relationships and mental well-being.

But there are spillover effects on physical health that are sometimes overlooked, according to the commission, which estimates the number of people with gambling disorder at 80 million globally and the number of those suffering from at least one ill-effect of gambling at over 400 million.

“Anyone with a mobile phone now has access to what is essentially a casino in their pocket, 24 hours a day,” said Heather Wardle of the University of Glasgow, the commission’s co-chair, accusing providers of deploying “highly sophisticated marketing and technology” and “design mechanics to encourage repeated and longer engagement.”

“Persuasive design techniques and interfaces are used to shape consumer behaviour and to maximise user engagement,” the commission said, pointing to data-driven algorithms which they said “are used to target the promotion of more attractive content to specific users.”

Phones and apps mean easy access to popular sports betting and online slot machines, including for children who would in the past have been too young to access bricks-and-mortar bookies or casinos.

“Children and adolescents are particularly vulnerable to the allure of easy money and the game-like designs of online gambling,” said Universitas Indonesia’s Kristiana Siste.