Free-to-play smartphone games featuring "unfair" in-app purchases have come under the scrutiny of the UK's Office of Fair Trading.
The OFT investigation is specifically to determine whether certain games are misleading and pressuring children to pay for content, and is seeking a response from parents who have experienced such issues.
The regulatory body is not looking into the practice of selling in-app purchases, but instead is looking at the way these are marketed to young players. The OFT is attempting to ascertain how aggressively certain titles encourage users to buy additional content, noting that certain actions could potentially be unlawful under UK law the 2008 Consumer Protection (from Unfair Trading) Regulations act.
"We are concerned that children and their parents could be subject to unfair pressure to purchase when they are playing games they thought were free, but which can actually run up substantial costs," said Cavendish Elithorn, the OFT's senior director for goods and consumer.
OFT statistics report that 80 of the 100 top-grossing applications on the Android market are free-to-play titles that make revenue through in-app purchases. Common methods of incorporating in-app purchases include selling virtual currency, consumable items, and new characters.
In February this year, five-year-old Danny Kitchen made headlines after running up a £1,700 bill playing the free-to-play game Zombies vs. Ninjas on his parents' iPad.
Elithorn says that the OFT is not looking to ban the act of in-app purchases, but that "the games industry must ensure it is complying with the relevant regulations so that children are protected."
"We are speaking to the industry and will take enforcement action if necessary."
The OFT says it will report on its findings in October 2013 and cannot currently name the companies and titles that are being investigated.