Apple and Google have agreed to initial commitments with the UK’s competition regulator to make their app stores more fair and transparent for developers, under measures intended to protect the smartphone app ecosystem.

The Competition and Markets Authority (CMA) said the two companies had agreed to ensure their store rankings and reviews operated fairly, would not give preferential treatment to their own apps, and would improve transparency around how apps are approved for sale.

The companies also said they would not use data gathered from third-party app developers to harm competition.

Apple agreed to allow outside developers to request access to more features in its iOS platform to create competing products, such as digital wallets or translation tools.

The commitments come after the Competition and Markets Authority (CMA) last October designated the two companies as having strategic market status (SMS) in the smartphone market.

The CMA said at the time that Apple and Google held an “effective duopoly” in the UK smartphone market.

The two companies have warned the CMA not to try to impose restrictive measures that could harm their business models, as they claim the European Union has done.

By contrast, the CMA said it is taking a collaborative approach and agreeing to measures with the companies, rather than imposing rules.

It said it would monitor the companies’ actions and could take further action if they fail to address complaints around the way apps are approved for sale, lack of access to iOS features, or other issues.

As yet, however, the agreements do not address key areas such as the commission fees imposed on in-app sales or the ability to install third-party app stores that bypass the companies’ official app stores entirely.

The CMA said on Tuesday that commission levels remained a priority, but that changes needed to reflect steps taken in other jurisdictions, and that it was continuing to engage with Apple and Google on the issue.

“These are important first steps while we continue to work on a broad range of additional measures to improve Apple and Google’s app store services in the UK,” said CMA chief executive Sarah Cardell.

Apple said it “appreciated the positive and ongoing dialogue” with the CMA, while Google welcomed the “opportunity to resolve the CMA’s concerns collaboratively”.