The trend toward browsing from phones and tablets has helped some browser makers, dramatically in one case, but hurt others in the battle for usage share, data from a metrics firm showed.
According to Net Applications, 12% of all browser use last month originated on mobile devices, which the Web analytics company defined as smartphones and tablets.
While down from the 13.2% of February, mobile's contribution in March was more than enough to show which browser vendors have benefited from the shift to mobile and which have not.
Creating a combined share of desktop plus mobile more accurately conveys each browser maker's total reach. And while such calculations do not alter the relative position of browsers, they do illustrate which punch above their desktop weight -- the number most cited by media reports -- and which are held back for lack of traction in mobile.
Microsoft's Internet Explorer (IE) and Mozilla's Firefox are the two browsers whose usage shares have been hit hardest by the trend toward mobile. That should not be a surprise, as Microsoft has been slow to turn to smartphones and tablets, and Mozilla has been virtually excluded from those devices.
Although IE continued to dominate the desktop, with a March share there of 55.8%, its minor presence in mobile lowered its combined share to 49.1%. Still the most-used browser, and by a wide margin, IE's desktop-plus-mobile share was again under the psychologically-important 50% bar last month.
Firefox's total share suffered from a paucity on mobile, too, but even more than IE: Mozilla has an Android version of Firefox in play, but its share was essentially zero. For March, Firefox's combined share was 17.7%, several percentage points lower than its desktop-only number.
Meanwhile, Apple and Google have leveraged their one-two positions in mobile to boost their combined shares.
Google, for example, had a combined usage share of 17.3%, nearly equal to Mozilla, because of its No. 2 spot in mobile generated by the Android and Chrome browsers. That's in contrast to Net Applications' estimate of Chrome's desktop share of 16.5%, nearly four points behind Firefox.
Apple, however, was the clear winner of mobile, with Safari's 61.8% share there boosting its browsers' combined share to 12.1%, making Safari a much stronger fourth-place rival to Chrome and Firefox than its puny desktop share has long suggested.
In fact, Apple was the only browser maker whose mobile component was larger than its desktop: Nearly two-thirds of Apple's total usage share came from Safari on iOS, where it's the default browser for iPhones and iPads.
Net Applications measures browser usage on smartphones, tablets and personal computers by tabulating approximately 160 million unique visitors each month who browse to the sites it monitors for customers. More information on usage shares can be found at its website.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, or subscribe to Gregg's RSS feed . His e-mail address is firstname.lastname@example.org.