What usability research reveals about default browser settings on iOS and Windows
The ability to choose a default browser is more than a technical setting—it’s a meaningful expression of user agency and an essential part of digital competition. But as our research shows, default browser settings that are technically available can still be practically out of reach for users.
Despite regulation like the EU’s Digital Markets Act (DMA), which mandates that users must be able to “easily change default settings” on operating systems, the actual implementation of browser default settings on iOS and Windows still presents significant barriers. Platforms may claim that their default browser settings are straightforward, but in practice, users face confusing menus, ineffective search, and interface designs that steer them toward platform browsers like Safari and Edge.
Mozilla’s multi-phase usability study reveals a clear gap between regulatory intent and user experience—one that undermines user choice and stalls competition.
What We Found
Across studies of iOS 17, iOS 18.2+, and Windows 10/11, participants consistently struggled with:
- Discoverability: Even when users knew what they were looking for, they often couldn’t find it—due to unintuitive menu structures, hidden options, or low-visibility interface elements.
- Search Failures: Common terms like “browser” and “default browser” frequently returned no results, forcing users into inefficient trial-and-error paths.
- Self-Preferencing Design: Both platforms steered users toward their own browsers—through misleading labels, prominent placements, or vanishing options.
- Mismatch Between Confidence and Reality: While participants generally believed they could change their defaults, most struggled and some gave up without completing the task.
Even with some changes in iOS 18.2+—such as a new “Default Apps” section and the removal of hidden options—discoverability and search remain major pain points.
Recommendations for Regulators and Platforms
- Centralize Access: Default browser settings should be available through clear, consistent, and easily accessible paths to eliminate navigation friction and align with user expectations—for example, restoring the “one click set to default” functionality on Windows.
- Fix Search: Ensure common search terms return relevant results and add features like typo correction, partial matches, and suggested alternatives.
- Avoid Interface Deception: End practices that hide, bury, or bias default browser setting options. Settings interfaces should present options clearly without hidden elements or misleading labels.
- Improve UI Visibility: Make settings stand out visually and match user expectations. Placement alone isn’t enough—design must support recognition.
- Transparency and Iteration: Gatekeepers should be required to test their compliance implementations with real users and share the results.
Bottom Line
Changing a default browser should take seconds, not have users resorting to trial-and-error, support documentation, or multiple failed searches.
Regulators should view usability as central to compliance. Mozilla’s findings show that without evidence-based implementation, even well-crafted regulations risk falling short. If users can’t easily act on their choices, then competition will continue to be impeded by powerful platforms.