Europe’s browser revolution appears to have left most browsers exactly where it found them. The European Commission is celebrating a “surge” in alternatives. The browsing data suggest a ripple.
In April, the Commission reviewed the Digital Markets Act (DMA) and pronounced it “fit for purpose.” “Alternative browsers and search engines are being increasingly chosen by users as defaults on their devices,” its announcement crowed. The review report went further: “alternative browsers have reported a surge in use thanks to choice screens”—prompts that ask users to choose a browser rather than stick with the preselected default. But the report offered no figures to show that surge.
Mozilla, which makes Firefox, stepped in to make the Commission’s case. The company counted more than six million Firefox selections through the DMA’s choice screens. It also publicized an estimate that Firefox use on iPhones was 113% higher in the European Union (EU) than it would have been without those screens.
Those numbers sure seem like a surge. We wanted to know how much of Europe’s mobile browsing actually moved.
Using public browser-share data from 11 countries, we found barely any movement. The default browsers’ combined share of mobile browsing changed by less than one percentage point. Firefox’s share rose by between one-fifth and two-fifths of a percentage point.
Meet the New Default, Same as the Old Default
Article 6(3) of the DMA requires designated operating systems and browsers to prompt users to choose a default browser and search engine from a list of major providers. The premise is simple: Many people use Safari or Chrome because it came with their phone. Asking them to choose might loosen that hold.
Apple introduced its EU browser-choice screen with iOS 17.4 in March 2024. With iOS 18.2, released that December, the screen appeared again for EU users who still had Safari as their default, the first time they opened Safari after updating.
Google began rolling out browser- and search-choice screens on Android in the European Economic Area (EEA) in March 2024. It separately planned an April rollout of a search-engine-choice screen in Chrome on desktop and iOS. The lists included Firefox, Opera, Brave, Edge, Ecosia, and DuckDuckGo, among others.
But a choice does not necessarily mean a shift away from the dominant browsers. Chrome also appears on Apple’s choice screen, so an iPhone user who swaps Safari for Chrome moves from one dominant browser to another. We therefore group Safari, Chrome, and Samsung Internet—the three browsers that come preinstalled on most phones—as “the defaults” and ask whether their combined share fell.
A Difference Without Much of a Difference
The obvious starting point is to compare the defaults’ share before and after the choice screens.
In six large EU countries—Germany, France, Italy, Spain, Poland, and the Netherlands—Safari, Chrome, and Samsung Internet together accounted for 96.0% of mobile page views in the two years before March 2024. Afterward, their combined share fell to 95.3%, a drop of 0.7 percentage points.
But browser shares move for reasons that have nothing to do with regulation. New phones ship, apps update, and habits change. Europe’s before-and-after comparison therefore mixes the choice screens’ effect with changes that would have happened anyway.
To separate the two, we compare Europe with five countries that experienced those broader changes without DMA choice screens: the United Kingdom, the United States, Switzerland, Canada, and Australia. None is subject to the DMA. There, the defaults’ share fell from 97.5% to 96.9%—a drop of 0.6 percentage points, without the regulatory nudge.
The estimated effect of the choice screens is the difference between those two drops: about 0.1 percentage point. Researchers call this method “difference-in-differences” (DiD). Its key assumption is that, without the screens, browser shares in Europe would have followed the same trend as in the comparison countries.
Our data come from StatCounter, which tracks page views on websites that carry its tracking code. It counts page views, not users, so heavy browsers carry more weight than occasional ones. These may not be the best data, but they are the best available. U.S. courts have also cited them in Lau v. Opera and the Google Search case, United States v. Google LLC.
The Surge That Barely Registered
Did the default browsers lose ground? Barely, if at all.
We estimate that the choice screens cut the defaults’ combined share of EU mobile browsing by 0.17 percentage points, from a starting point of 96%.
Monthly data are noisy, so a range tells us more than a single estimate. The 95% confidence interval runs from a loss of 1.2 percentage points to a gain of 0.8. In other words, the data are consistent with a small decline, no change, or even a small increase.
Even the largest decline within that range would shift only about one percentage point of mobile browsing away from the defaults. And “decline” is doing some heavy lifting: The estimated effect is not statistically distinguishable from zero.
The rival browsers that StatCounter reports separately tell the same story. Firefox, Opera, Brave, Edge, and Ecosia together accounted for 2.6% of EU mobile page views before the choice screens. We estimate that the screens added 0.2 percentage points, with a range from a loss of 0.6 to a gain of 1.0—again, not statistically distinguishable from zero. DuckDuckGo also appeared on the screens, but StatCounter does not report its browser separately.
Figure 1. Source: StatCounter Global Stats, mobile browser market share, January 2022–September 2026. EU: Germany, France, Italy, Spain, Poland, and the Netherlands. Comparison countries: United Kingdom, United States, Switzerland, Canada, and Australia.
Figure 1 tracks the rivals’ combined share month by month. It rose in Europe after March 2024. But it had already been rising for two years, and it also rose in the comparison countries, without DMA choice screens.
Firefox gained some ground. Across the six EU countries, its share rose from 1.02% of mobile page views before the screens to 1.31% afterward. In the comparison countries, it rose from 1.08% to 1.15%. The difference between those gains is 0.22 percentage points.
Restricting the analysis to the months after Apple’s December 2024 update—which showed the screen again to EU users who still used Safari as their default—produces much the same result: a decline of 0.15 percentage points for the defaults and a gain of 0.10 for the rivals. Separate estimates for Safari and Chrome are too imprecise to draw conclusions: Each browser’s share could have moved four to seven percentage points in either direction.
Big Gains, Tiny Footprint
Why do the percentages sound so big? Because Firefox started from almost nothing.
Relative to the comparison countries, its share of EU mobile page views rose about 23%. Our most generous estimate, which also accounts for changes in Firefox’s desktop use in the same countries, puts the gain at 37%. From a starting share of about 1%, those gains amount to just 0.2 to 0.4 percentage points.
Mozilla’s research finds larger percentage gains. A paper by Jesper Akesson and colleagues, two of whom work at Mozilla, uses the company’s own Firefox usage data from 27 EU countries and 43 others. It finds that, from the 15th month onward, Firefox use was 91% higher on iOS and 13% higher on Android than it would have been without the choice screens. The paper’s first version, released in April, put the iOS gain at 113%.
Mozilla measures Firefox use directly, something StatCounter cannot do. Our estimate combines iPhones and Android phones and falls between the paper’s two platform-specific figures. The paper also reports that, in market-share data, Safari’s losses on iOS went mostly to Chrome.
Figure 2. Sources: StatCounter Global Stats (Firefox’s pre-screen share, six EU countries, January 2022–February 2024); authors’ estimates; Akesson et al., National Bureau of Economic Research (NBER) Working Paper No. 35112 (revised July 2026).
Figure 2 translates those percentage gains into shares of all mobile browsing. Even applying the 91% iOS gain to Firefox’s entire mobile share would leave it below 2%. The three defaults would still account for about 95%.
Mozilla’s six million selections tell us how often users picked Firefox, not whether they kept using it. Someone who picks Firefox on the choice screen may return to Safari a week later; a selection count cannot tell us how many did. That makes the NBER paper’s usage figures, measured more than a year later, more informative than the tally of clicks.
Mind the Error Bars
How sure can we be? Less sure than the confidence ranges suggest, for three reasons.
First, country-level figures can jump for reasons StatCounter does not disclose. In Germany, Chrome’s share of desktop page views rose from 51% to 66% between January and March 2025, then fell to 54% by July—even though no browser-choice screen appeared on desktop. Nothing similar happened in the other 10 countries. That suggests a change in the German websites StatCounter samples rather than in Germans’ browsing habits, although we cannot rule out a real shift.
Second, Europe and the comparison countries were already diverging before March 2024. Figure 1 shows the rivals’ EU share pulling ahead during 2023. If that trend would have continued without the screens, we may be crediting them for gains that would have happened anyway.
Third, page views are not people. A heavy Safari user carries more weight than an occasional Firefox user. And 11 countries make a small statistical sample, which helps explain our wide ranges.
The data can rule out a large shift away from the default browsers. They cannot establish a small one.
Third Time’s the Same
Haven’t we seen this before? Yes—twice.
In 2009, Microsoft settled the Commission’s case over bundling Internet Explorer with Windows by agreeing to show European users a browser-choice screen for five years. Omar Vásquez Duque estimates that its effect on Internet Explorer was “negligible (roughly, between 1.4 and 2 percent).” Because his estimates measure differences in market share, those figures represent percentage points. Geoffrey Manne and Joshua Wright found that Internet Explorer’s European share tracked its worldwide share, where users saw no choice screen, and that its decline tracked Chrome’s rise.
After the Commission’s 2018 Android decision, Google began showing a search-engine-choice screen on new Android phones in Europe. Francesco Decarolis and Muxin Li report that Google’s share of EEA mobile search fell from 98.58% in March 2020 to 97.66% in August 2022—less than one percentage point.
For the DMA screens, Vásquez Duque uses StatCounter data and a different statistical method. He finds that Chrome’s share fell about 1.8 percentage points, while Firefox and Opera gained “below 0.5%.” Our Chrome estimate is about the same size, but too imprecise to distinguish from zero.
Three rounds of choice screens over 15 years. Three small effects.
Please Select a Definition of Success
What would success look like? The Commission’s review never says. It reports that users are choosing alternatives and that rival browsers claim a surge, then stops there. As one of us argued when the review appeared, the regulator is grading its own homework.
Counting choices is not the same as evaluating a remedy. A screen that shifts one-fifth of a percentage point of browsing could be worthwhile if switchers get a better experience and everyone else bears little cost. The trade looks worse if most switchers drift back, or millions of people sit through a prompt that produces a change too small to measure.
No published study settles that question. Neither market shares nor selection counts tell us whether switchers are better off. Two kinds of evidence would help:
- Retention. How many people who picked a rival browser still use it a year later? Mozilla and other browser makers have those numbers for their own products.
- Satisfaction. Do switchers report a better experience than they had before? A survey could measure that.
Until that evidence appears, the fair summary is modest: Firefox gained a fraction of a percentage point of mobile browsing, and the defaults kept about 95%. Large percentage gains from a tiny starting share do not change that picture.
The Commission is already pressing gatekeepers—the large platforms subject to the DMA—to make default settings easier to change for artificial intelligence services. Before extending the choice-screen approach, it should define success and let someone else check the results.
More prompts are not proof of progress.
