Should Apple keep blocking competing browser engines on iOS?

Apple forces all apps that access the web in iOS and iPadOS to use its own browser engine, WebKit, but should it continue to effectively restrict other browser engines despite claims of anti-competitive behavior? In a news release, Andrea Coscelli, Chief Executive of the UK’s Competition and Markets Authority (CMA), said:

“Apple and Google have acquired a vice-like hold over how we use mobile phones, and we’re concerned that it’s leading millions of people throughout the UK to lose out.”

Among the claims of anti-competitive behavior, Apple has been chastised for requiring web-browsing apps on iOS and iPadOS to use the WebKit framework and WebKit Javascript, thereby excluding non-WebKit-based browsers. 2.5.6 Apps that surf the web must use the appropriate WebKit framework and WebKit Javascript, according to Apple’s App Store Review Guidelines.

Regulatory agencies have taken notice of Apple’s WebKit policies, including the CMA, which has harshly condemned the restriction:

We have found that by requiring all browsers on iOS devices to use its WebKit browser engine, Apple controls and sets the boundaries of the quality and functionality of all browsers on iOS. It also limits the potential for rival browsers to differentiate themselves from Safari. For example, browsers are less able to accelerate the speed of page loading and cannot display videos in formats not supported by WebKit. Further, Apple does not provide rival browsers with the access to the same functionality and APIs that are available to Safari. Overall, this means that Safari does not face effective competition from other browsers on iOS devices.

The evidence also suggests that browsers on iOS offer less feature support than browsers built on other browser engines, in particular with respect to web apps. As a result, web apps are a less viable alternative to native apps from the App Store for delivering content on iOS devices.

The CMA stated that app developers are unable to distinguish their browsers from Safari, whereas web developers are limited to the functionalities supported by WebKit.

Importantly, due to the WebKit restriction, Apple makes decisions on whether to support features not only for its own browser, but for all browsers on iOS. This not only restricts competition (as it materially limits the potential for rival browsers to differentiate themselves from Safari on factors such as speed and functionality) but also limits the capability of all browsers on iOS devices, depriving iOS users of useful innovations they might otherwise benefit from.

Apple’s long-standing refusal to enable app sideloading on iOS and iPadOS is also at the center of the argument. Outside of top-level games, Apple’s WebKit restriction and control over Safari is the sole practical impediment to developers launching web apps for iOS and iPadOS that are indistinguishable from native apps. Sideloading from the web becomes conceivable if developers can use a different browser to open web programs.

It’s also worth noting that the CMA rejects Apple’s contention that restricting web browsing on iOS and iPadOS to WebKit is better for efficiency and security:

Overall, the evidence we have received to date does not suggest that Apple’s WebKit restriction allows for quicker and more effective response to security threats for dedicated browser apps on iOS. the evidence that we have seen to date does not suggest that there are material differences in the security performance of WebKit and alternative browser engines.