When the book is finally closed on the product line known as OS X, last year’s release of OS X 10.9 Mavericks may end up getting short shrift. Sure, it brought tangible energy saving benefits to Mac laptop owners, but such gains are quickly taken for granted; internal changes and new frameworks are not as memorable to customers as they may be to developers and technophiles. And while Mavericks included many new user-visible features, and even new bundled applications, the cumulative effect was that of a pleasant upgrade, not a blockbuster.

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But for all its timidity and awkwardness, Mavericks marked a turning point for OS X—and in more than just naming scheme. It was the first OS X release from the newly unified, post-Forstall Apple. If iOS 7 was the explosive release of Jony Ive’s pent-up software design ethos, then Mavericks was the embodiment of Craig Federighi’s patient engineering discipline. Or maybe Mavericks was just a victim of time constraints and priorities. Either way, in last year’s OS X release, Apple tore down the old. This year, finally, Apple is ready with the new.

To signal the Mac’s newfound confidence, Apple has traded 10.9’s obscure surfing location for one of the best known and most beautiful national parks: Yosemite. The new OS’s headline feature is one that’s sure to make for a noteworthy chapter in the annals of OS X: an all-new user interface appearance. Of course, this change comes a year after iOS got its extreme makeover.

Ah, the old tension: which platform does Apple love more? iOS continues to dominate Apple’s business in terms of unit sales, revenue, and profits. Last year, some Apple watchers had openly wondered whether Apple would even bother updating the look of OS X. And yet for the past several years, Apple has loudly and publicly insisted that it remains committed to the Mac as a strong, independent platform. Yosemite aims to fulfill that commitment—but in an interesting way.

All together now

OS X and iOS have been trading technologies for some time now. For example, AVFoundation, Apple’s modern framework for manipulating audiovisual media, was released for iOS a year before it appeared on OS X. Going in the other direction, Core Animation, though an integral part of the entire iPhone interface, was released first on the Mac. Yosemite’s new look continues the pattern; iOS got its visual refresh last year, and now it’s OS X’s turn.

But at this year’s Worldwide Developers Conference, Apple made several announcements that point in a new direction: iOS and OS X advancing in lockstep, with new technologies that not only appear on both platforms simultaneously but also aim to weave them together.

These new, shared triumphs run the gamut from traditional frameworks and APIs to cloud services to the very foundation of Apple’s software ecosystem, the programming language itself. Apple’s dramatic leadership restructuring in 2012 put Federighi in charge of both iOS and OS X—a unification of thought that has now, two years later, resulted in a clear unification of action. Even the most ardent Mac fan will admit that iOS 7 was a bigger update than Mavericks. This time around, it’s finally a fair fight.

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