Chrome's 31 percent usage share on the desktop, for example, lagged behind IE's 43 percent, but Google's mobile browsers made up for that shortfall in spades. Safari's puny 10 percent on the desktop -- in fourth place in the U.S. -- was helped out of the cellar by Safari's 59 percent usage share on mobile.
Mozilla, Adobe said, was in the weakest position of the Big Four because of its lack of a viable mobile strategy. In the last two years, Mozilla has lost a steady drip of Firefox desktop users and been hit by the increasing importance of mobile browsing, with its total usage share falling from nearly 20 percent to its now sub-9 percent.
Although Net Applications' numbers are global and not U.S. specific -- the company does not publicly release the latter -- the trends shown by its data are similar to Adobe's.
But not identical.
By Net Applications' reckoning, Microsoft remained the top browser maker worldwide in May 2014 with a desktop + mobile user share of 48 percent, more than double that of runner-up Google and its 21 percent. Apple and Mozilla continued to battle for third place, with the former making strides in its move to pass the latter. In May, Firefox accounted for 13.8 percent, Safari for 13.4 percent. Safari cut the April gap between it and Firefox by more than half in May, and may become No. 3 as early as this month.
Firefox's decline could not come at a worse time. Mozilla's contract with Google for making the latter's search engine the default on Firefox comes up for renewal in November. According to Net Applications, Firefox had a combined desktop + mobile user share of 21.1 percent three years ago when it negotiated the current contract, which paid Mozilla approximately $300 million annually, nearly all of its revenue.
Going into this year's tete-a-tete with Google, Mozilla will be bargaining from a much weaker position, down 35 percent in total share since 2011.
Net Applications had mobile gaining more ground at the expense of desktop browsing in May. By the end of the month, mobile browsing had jumped to 18 percent of all browsing worldwide. At the current pace, mobile should reach the 20 percent milestone in October, and account for more than a quarter of all browsing by this time next year.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is firstname.lastname@example.org.
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