The UK's CMA has launched an investigation into whether Apple and Google hold strategic market status (SMS) in mobile ecosystems, including operating systems, app stores, and mobile browsers.

This falls under the newly passed Digital Markets, Competition and Consumers Act (DMCC), which came into force on January 1, 2025. The investigations place significant focus on web apps, browser engines, and browsers.

Being declared an SMS under the DMCC can be seen as equivalent to being designated a gatekeeper under the EU's Digital Markets Act (DMA).

Web apps, which are separate apps that can be saved to a user’s home screen from a browser, are generally not considered by app developers to be a realistic alternative to listing native apps on the App Store, due to the limited features and functionalities available for web apps on iOS; which in turn, is determined by Apple through rules that require all browsers on iOS to use its own browser engine, WebKit. Apple SMS Investigation

Apple’s requirement that all mobile browsers on iOS use its WebKit browser engine also means that WebKit does not face any competition from rival browser engines on iOS. Apple SMS Investigation

As a result of the Android Licence Agreements between Google and OEMs, Google’s Chrome is pre-installed, prominently placed, and set as the default mobile browser for many Android devices, creating barriers to entry and expansion for competing mobile browsers. Google SMS Investigation

The Digital Markets, Competition, and Consumers Act 2024 came into effect on January the 1st 2025, granting the UK regulator authority to designate companies with Strategic Market Status (SMS).

This can be thought of as the UK’s equivalent to the EU’s Digital Markets Act, although it has differences in how it is implemented as covered in this article. The DMCC (the written UK Act) mostly leaves it up to the CMA (the agency) to decide what rules are appropriate to impose; the DMA (the written EU Act) dictates it rules with significantly less room for flexibility

Firms with Strategic Market Status (SMS) designation will be required to adhere to one or more tailored conduct requirements (CRs). The DMCC Act provides a structured framework for the Competition and Markets Authority (CMA) to follow when implementing these requirements.

Non-compliance with a conduct requirement could result in substantial penalties, amounting to up to 10% of the company’s global turnover. It will likely take until the end of the year (9 months from initiation) to designate the first batch of SMS companies.

As readers may recall, the UK Competition and Markets Authority launched a Market Investigation Reference (MIR) into mobile browsers and cloud gaming on June 10th 2022.

From our extensive work in supporting the Mobile Ecosystems Study, we know the key reason the Market Investigation Reference into Browsers and Cloud Gaming was launched was to enable the free, open and interoperable ecosystem of the web to contest Apple’s and Google’s app stores, reducing costs for UK’s consumers and businesses. While regulators across the world were focused on app stores, the UK was the only regulator that was looking towards the web and web apps to solve these issues on mobile ecosystems. This aim was made clear by the opening statements of the Browsers and Cloud MIR:

We all rely on browsers to use the internet on our phones, and the engines that make them work have a huge bearing on what we can see and do. Right now, choice in this space is severely limited and that has real impacts – preventing innovation and reducing competition from web apps. We need to give innovative tech firms, many of which are ambitious start-ups, a fair chance to compete. Andrea Coscelli - Chief Executive of the UK's Competition and Markets Authority
(emphasis added)

For example, ‘equivalence of access’ would need to include enabling third-party browsers using alternative browser engines to install and manage PWAs (rather than relying on WebKit to support parts of this process), including enabling mobile browsers using alternative browser engines to implement installation prompts for PWAs. MIR - Provisional Decision Report
(emphasis added)

While a very crude measure, “web app” was mentioned 300 times in the provisional decision report.

In the provisional decision report, the MIR team has opted not to use the powers of the MIR but instead to hand over its findings to the CMA who will use the DMCC as the enforcement and oversight mechanism.

In order to enforce any of the remedies of the MIR under the DMCC on Apple and Google, Apple and Google must first be declared SMS under the DMCC. To do this, the CMA needs to hear from you about your views on browsers, browser engines, and web apps; please consider responding to this request for comment.

See the file on the Google investigation.

See the file on the Apple investigation.

Anyone with an interest in these investigations is invited to comment until Wednesday 12 February.

Stay tuned as Open Web Advocacy takes a closer look and shares deeper insights over the coming weeks: