The tech giant could be compelled to allow competing app stores within the United Kingdom.
Apple may have to allow rivals to operate separate app stores on Apple devices across Britain, after a ruling from the competition regulator.
This would be a major shift to the company's well-known "closed system" where apps can only be downloaded from the company's App Store.
But the UK competition watchdog has classified both the tech giants as having "dominant market position" - effectively saying they have significant control over mobile platforms.
Regulatory Findings
The regulator said the tech firms "may be limiting innovation and market rivalry".
But the regulator clarified it did not "find or assume misconduct" from the companies.
"Mobile applications generates one and a half percent of the UK's GDP and supports around four hundred thousand positions, which is why it's essential these sectors function properly for enterprises," commented a senior official from the competition authority.
Approximately ninety to one hundred percent of British smartphones run on Apple or Google's operating systems, creating what the regulator calls an "virtual monopoly".
Based on recent analysis, nearly half of British smartphone users own an Apple device - which runs Apple's iOS - with the vast majority of the rest using the Android OS.
Apple's Response
The CMA's investigation focused on how dominant the companies' own apps are versus competitors - as well as their web applications and operating systems.
It is unclear what modifications the authority will seek to implement, but previously it published guidelines detailing potential measures it could take.
These comprise mandating it to be more straightforward for people to switch between Apple and Android phones, and for both companies to rank apps "in a fair, objective and transparent manner" in their marketplaces.
The Cupertino company specifically may be compelled to allow alternative app stores on its products, and let people to download programs straight from companies' websites.
This would follow comparable regulations in the EU, which previously took action against Apple for anti-competitive behaviour.
Apple cautioned the United Kingdom could face delays to getting new features - as has occurred in the European Union - which the organization attributes to heavy regulation.
For instance, some AI features which have been launched in other parts of the world are not accessible in the EU.
"We faces fierce competition in every sector where we do business, and we strive continuously to create the finest offerings, services and customer interface," the company said in a release.
"Britain's implementation of European regulations would weaken that, leaving users with weaker privacy and security, slower availability to new features, and a fragmented, less seamless user journey."
The Search Giant's Position
Android users can presently use alternative marketplaces - though commentators say they are not as smooth as the company's official application marketplace.
The CMA's roadmap said the search company may have to "modify the interface" of installing applications directly from online sources, as well as "remove user frictions" when using alternative app stores.
"There appears to be no the justification for today's designation decision," a Google competition lead remarked.
The executive said "the majority" of Android users use alternative app stores or download apps straight from a creator's site, and asserted there is a far greater range of apps offered for Google device owners versus those on iOS products.
"There are now 24,000 Android phone models from 1,300 phone manufacturers worldwide, facing strong rivalry from iOS in the United Kingdom," the representative continued.
Android is an freely available software, which means creators can utilize and develop on top of it for free.
Google contends this means it opens up competition.
But consumer groups said restrictions on these companies' power in other countries "are already helping businesses to innovate and giving customers more options".
"Their dominance is now causing real harm by limiting options for consumers and market rivalry for companies," commented a policy expert.