The United Kingdom competition watchdog is moving to curb the dominance of Apple and Google over mobile platforms by proposing rules that would allow app developers to direct users to alternative payment options outside their app stores.

The Competition and Markets Authority said restrictions imposed by Apple and Google prevent consumers and developers from making purchases beyond their app stores, limiting competition and choice.

According to the regulator, the two companies operate an “effective duopoly,” with more than 90 per cent of mobile devices in the UK running on their platforms.

The CMA said removing barriers to “steering,” allowing apps to guide users to external websites for purchases, would promote greater competition and reduce developers’ reliance on Apple and Google’s app stores.

The watchdog is now consulting on proposals to lift those restrictions, a move it says would enable developers to avoid the mandatory fees charged through the two companies’ app marketplaces.

Apple and Google currently charge commissions of up to 30% on in-app purchases, including subscriptions. Google said it has already introduced changes that allow developers to direct users outside the Play Store to complete transactions.

The existing rules have affected services such as Spotify, which does not offer users the option to purchase monthly subscriptions through Apple’s App Store in the UK. Instead, customers must subscribe through Spotify’s website to avoid Apple’s commission fees.

The CMA’s Executive Director for Digital Markets, Will Hayter, said giving developers and consumers greater freedom over how they communicate and complete transactions would encourage competition and provide more choice.

“This is not only because choice is inherently valuable but also because we see this as the best way to introduce some competitive pressure in a vital part of the mobile ecosystem that is otherwise sorely lacking such pressure,” he said.

The CMA said Apple and Google could still charge developers fees for allowing apps to direct users to alternative payment methods, but such charges must be fair and proportionate. Google said it has already introduced revised fee structures, including charges related to steering users to payment options outside the Play Store.

Meanwhile, the Coalition for App Fairness, whose members include Spotify and Match Group, criticised the proposal to permit steering fees. The group argued that any such charges should be backed by transparent data showing the actual costs incurred by Apple and Google in supporting those transactions.