Campaigners urge crackdown after user says they were shocked to see offers of free bets

Adverts for the bookmaker Ladbrokes have been shown to “exhausted parents” via a smartphone app that can be used as a baby monitor, the Guardian can reveal.

Campaigners have responded by calling for urgent action to reform the rules governing gambling advertising, which have so far been left out of plans to overhaul regulation of the £11bn-a-year sector.