Last week, The Register reported that Google’s Chromium team has begun developing an iOS browser based on the open-source Blink browser engine. And yesterday, The Register ascertained from a GitHub commit that Firefox may be developing an iOS browser based on that company’s Gecko browser engine.
Neither of these browsers would survive the current App Store review process because Apple’s developer guidelines prohibit browser apps, or “apps that browse the web,” from using any browser engine other than Apple’s WebKit. Specifically, guideline 2.5.6:
WebKit is the browser engine on which Safari is built. A browser engine interprets HTML and other stylistic components of a website and renders them into user-accessible content; a separate, JavaScript engine executes JavaScript code. Note that until late 2020, with the release of iOS 14, Apple did not allow users to select a default browser other than Safari.
But the distinction between browsers on iOS is mostly illusory, anyway. Because all browsers on iOS are forced to use WebKit, they all mostly feature the same functionality and only substantively differ in terms of aesthetics and native connectivity to third-party services (eg. Chrome and Google profiles). Alex Russel has written a masterful multi–part series on why Apple’s restriction of browser engines to WebKit is problematic (this presentation of his summarizes his points in 30 minutes).
The UK’s Competition and Markets Authority (CMA) dedicated an appendix to browser engine choice in its recent Mobile ecosystems market study. In that appendix, the CMA notes that Safari lags other browsers in terms of compatibility:
The yellow Safari line (which represents any browser built on WebKit) is substantially and persistently higher than the blue Chrome and red Firefox lines (representing browsers built on Blink and Gecko respectively). This indicates that WebKit has performed significantly worse in terms of compatibility than Blink and Gecko over this period.
The CMA also finds that Apple updates Safari on iOS about half as frequently (every 20 days) as Google updates Chrome on Android (10 days):
In the full, final report, the CMA presents this graphic, which showcases feature compatibility across different browsers (Safari at the left on iOS; Firefox on Android in the middle; and Chrome on Android at the right):
The CMA’s report surmises that Apple is advantaged through its restrictions on alternative browser engine use on iOS in two primary ways:
- Forcing the use of WebKit prevents alternative browsers from achieving meaningful differentiation from Safari, and because Safari is pre-loaded onto iOS and is also set as the default browser, consumers have little incentive to adopt alternative browsers. The CMA proposes that this dynamic protects Apple’s revenue share agreement with Google, which generates an estimated $8-12BN in revenue for Apple per year by establishing Google as the default search engine in Safari;
- Because WebKit functionality is more limited than that of other browser engines, the requirement to use WebKit confers functional superiority to native iOS apps, the distribution of which Apple controls through the App Store. Apple takes a commission on in-app payments in native iOS apps (and it also operates an app advertising network), but Apple can’t monetize consumer use of progressive web apps.
Per the CMA’s report, Apple justifies its requirement that iOS browsers utilize WebKit on grounds related to security and privacy:
Given this history as well as Apple’s pretextual defense of the practice of requiring WebKit’s use in iOS browsers, why are Google and Firefox pursuing these browser projects on iOS now?
Likely because the Digital Markets Act (DMA), which was adopted by the European Parliament in July 2022, goes into effect in the EU soon. The DMA primarily relates to competition in digital markets, and it addresses competition-suppressing tactics by so-called gatekeepers such as storefront limitations (eg. Apple’s “no-app-stores-in-the-App-Store” policy) and alternative payments. I’m skeptical that forcing platform operators to allow for alternative, in-app payments will materially impact the app economy, given how ingrained the use of default payments methods is, as well as Apple’s intransigence on the matter.
Nonetheless, as I detail in The app economy’s Perestroika, the steady drumbeat of legislation and regulatory interventions into mobile platform operating models is clearly trending in the direction of greater levels of concrete and credible competition. Apple reportedly began preparing for the eventual introduction of alternative app stores on iOS at the end of last year; with respect to browser engines, Google and Mozilla seem to envision a (likely near-term) future in which their browsers are not tethered to Apple’s WebKit.
The first browser war was fomented in the early 1990s by the advent of the World Wide Web and the HTTP protocol; the second browser war was instigated by new web standards, the availability of on-page, asynchronous interactive functionality afforded by various JavaScript frameworks, and the introduction of Google’s Chrome browser (Mozilla’s CTO proclaimed in 2017 that Chrome “won” the second browser war).
The third browser war might be instigated by the opportunity unlocked through regulatory intervention on iOS: if Apple is forced to relent on WebKit’s use in all browsers on iOS, a race to capture mobile web engagement may ensue.