Apple's OS X Yosemite continued its rapid pace of adoption in the second month after release, with uptake exceeding that of any of its predecessors, according to data from analytics vendor Net Applications.
The numbers hint that as Apple's 2013 decision to give away upgrades becomes the norm, future OS X adoption will increase in speed.
For December, Yosemite accounted for 45% of all instances of OS X tallied by Net Applications, which estimates operating system user share by counting visits to the websites that deploy its metrics package. It was the first time that Yosemite became the most popular OS X edition.
Apple released Yosemite to the Mac App Store on Oct. 16, 2014.
By comparison, OS X Mavericks, an October 2013 upgrade, ended December of that year with a user share of 37%. Mountain Lion, released in 2012 and Apple's last upgrade with a price tag, ended its second month post-launch at 26%. Mavericks and Mountain Lion took 4 and 12 months, respectively, to reach Yosemite's two-month mark.
Although Yosemite had a head start -- unlike Mavericks, Yosemite was offered to Mac owners as a beta for several months before launch -- the preview no longer was the cause of the gap. The eight-point difference between the two was double the four points provided by Yosemite's beta before official release.
Yosemite's brisk uptake tempo also indicated that even though many have questioned Apple's software quality and called for the Cupertino, Calif. firm to slow down its release pace, large numbers of Mac owners continued to upgrade. Net Applications' data tells nothing about customer satisfaction with Yosemite, of course; rolling back to an earlier version after upgrading requires a back-up and more time than most people would want to spend.
What is clear is that Apple's bet on free OS X upgrades has been successful at moving more Mac users to the newest edition faster than did even low-priced upgrades.
Apple's experience could influence how Microsoft decides to handle Windows 10 upgrades if, as some suspect, the Redmond, Wash. company's goal is to quickly get as many as possible onto the new OS so they can become potential buyers of apps, add-ons and services.
According to Net Applications, one in five Macs ran an unsupported edition of OS X in December, about the same percentage as the month before. Apple has dropped security support for 2011's Lion and earlier versions, meaning those editions no longer receive vulnerability patches.
Yosemite can be downloaded from Apple's Mac App Store, and supports Macs up to seven years old.