Safari's Default Dominance: How Apple Blocks Browser Competition on iOS

Every web browser available on iOS — Chrome, Firefox, Edge, Brave — is required to use Apple's WebKit rendering engine. This means that despite their different interfaces and features, every iOS browser is fundamentally Safari underneath, subject to Safari's limitations, bugs, and performance characteristics. This requirement effectively eliminates browser engine competition on the platform with the highest per-user spending in mobile computing.

The WebKit Monopoly Effect

Apple's WebKit requirement means that web features supported in Chrome on Android — including Progressive Web Apps, push notifications (until recently), and various modern APIs — are unavailable or degraded on iOS regardless of which browser users choose. Developers who want their web apps to work well on iPhones must build for WebKit's limitations rather than leveraging the full capabilities of modern browser engines. This creates a structural disadvantage for web-based applications compared to native iOS apps distributed through Apple's App Store — where Apple collects its 30% commission.

The Conflict of Interest

Apple has a direct financial interest in keeping web apps inferior to native apps. Every app distributed through the web avoids Apple's App Store commission. If iOS allowed browser engines that fully supported Progressive Web Apps, background processing, and hardware access, developers could distribute sophisticated applications through the web without paying Apple's fees. The WebKit requirement ensures the web remains a second-class platform on iOS, funneling developers toward the App Store where Apple extracts revenue.

The EU's Digital Markets Act has forced Apple to allow alternative browser engines on iOS in Europe, though Apple has imposed conditions that browser vendors call deliberately burdensome. The initial implementation required alternative engines to run in a restricted sandbox with limited performance capabilities, effectively maintaining WebKit's advantages through regulatory arbitrage rather than genuine compliance.

For web developers, the WebKit monopoly means building for iOS requires testing against Safari's specific implementation rather than web standards. Users seeking genuine browser choice should advocate for extending the EU's alternative engine requirements to other markets, and developers should support the open web by building standards-compliant applications that put pressure on Apple to improve WebKit's standards compliance and feature parity.