The games targeted by the investigation have not been named, reports the BBC, but are three among many.
The topic is high on government agendas after a series of cases where children spent thousands of pounds on online or app-based games. The European Commission has asked Apple and Google to address the issue. Both have agreed to strengthen payment authorisation and stop manufacturers describing games as "free" if they contain in-game or in-app purchases.
The UK government has also published a PDF guide for parents and carers, to help ensure they don't get ripped off by unscrupulous publishers.
These games may sometimes encourage children to make in-play purchases, including buying items or content needed to continue playing.
After you buy or download a game, if you haven't updated your device settings it may allow your child to make in-play purchases without entering a password.
Top tips to help you avoid problems:
• check your device settings
• familiarise yourself with the game
• check your billsCheck how the device is set up.
Before you let your child use the device, check your purchase settings to prevent them spending money without you knowing and don't share your password.Read all about it.
Before you or your child download a game, check the description to make sure you're happy for your child to play. It should tell you about the game's main characteristics, payment arrangements and who to contact if you have any questions or want to complain.How much?
Check your bills to see if money has been taken from your account without your knowledge or consent. If it has, get in touch with the game operator or platform provider.For more information about the CMA's work in this sector www.gov.uk/cma-cases/children-s-online-games
