The UK’s competition watchdog has launched investigations into the impact of Apple and Google’s mobile platforms on consumers and businesses, days after the government faced criticism for installing a former tech executive as the organisation’s new chair.

The Competition and Markets Authority (CMA) will investigate the tech firms’ mobile operating systems, app stores and browsers to determine whether both companies require tailor-made guidelines to regulate their behaviour.

The move follows the government denying it was “in the pocket of big tech” after appointing Doug Gurr, a former country manager of Amazon UK, to chair the CMA.

The CMA said it would look at the impact of Google and Apple’s mobile platforms on consumers and businesses, including app developers.

The watchdog said virtually all smartphones sold in the UK were pre-installed with Apple’s iOS or Google’s Android operating systems, while their respective app stores and browsers had privileged positions on their platforms compared with third-party products and services.

The CMA will determine whether Apple and Google should be designated as having “strategic market status” under a new regulatory regime brought in under the Digital Markets, Competition and Consumers Act 2024. If they are deemed to have that status, the watchdog can impose “conduct requirements” or force changes such as making it easier for users to download apps outside Apple and Google’s own app stores.

Sarah Cardell, the CMA’s chief executive, said both companies’ mobile platforms were consumers’ gateways “into the digital world”.

“More competitive mobile ecosystems could foster new innovations and new opportunities across a range of services that millions of people use, be they app stores, browsers or operating systems,” she said. “Better competition could also boost growth here in the UK, with businesses able to offer new and innovative types of products and services on Apple’s and Google’s platforms.”

The CMA said it would complete its investigation by 22 October. Last week, it opened its first investigation under the new legislation into Google and the impact of the company’s search and advertising practices on consumers, news publishers, businesses and rival search engines.

Alex Haffner, a partner at the UK law firm Fladgate, said the Apple and Google move was “wholly expected” but was taking place against a policy backdrop of a government seeking strong economic growth.

“What is more interesting is how this fits into the very clear steer the CMA is getting from central government to ensure that regulation is consistently applied with its pro-growth agenda,” he said.

On Wednesday, the business minister Justin Madders said the government had not been captured by big tech after appointing Gurr. Speaking in parliament, Madders said: “Competition is vital for driving investment and growth and the operational independence of the CMA will remain in place.”

The GMB union criticised Gurr’s appointment, describing it as a “slap in the face to workers”, while Ethical Consumer, a campaigning consumer cooperative, said it was “like something out of the Donald Trump playbook”.

Google’s senior director of competition, Oliver Bethell, said Android was the “only example” of a successful open-source mobile operating system, meaning it is freely available to developers.

He said: “We favour a way forward that avoids stifling choice and opportunities for UK consumers and businesses alike, and without risk to UK growth prospects.”

Apple said its app store ultimately supported hundreds of thousands of UK jobs and the company would “engage constructively” with the CMA. An Apple spokesperson said: “We face competition in every segment and jurisdiction where we operate, and our focus is always the trust of our users.”