Apple once maintained a single operating system. Then came the iPhone, and it became a two-OS company. Apple's forays into the adjacent categories of TV platforms and smartwatches yielded their own OSes. And if you knew that Apple would launch a fifth OS at this year's WWDC, the likely candidate would be "AudioOS" to prep the AirPods and HomePod for a range of services or Amazon Echo-like skills based on Siri.
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But no. Apple's new OS serves iPads, a category of devices that's been around for a decade and seen significant volume drops in the past years that have not fazed Apple. They grew and shrunk on the back of a mobile phone operating system, albeit one that was increasingly offering additional features for the iPad. These began to steer the iPad's identity into a more bona fide alternative to Macs and PCs. The 12.9-inch iPad Pro began offering a MacBook display-rivaling expanse. And Apple made its strongest push ever for desktop-like apps at the launch of the second-generation iPad Pros last year, with the announcement that "real" Adobe Photoshop would be coming to the platform. Those iPads also brought the adoption of USB-C, a functional improvement and symbolic shift away from the iPhone legacy of proprietary connectors.
And at this year's WWDC, iPadOS pushed its host device even further on its journey to mainstream laptop replacement. Behold the use of flash drives, an improved Files app that offers Finder-like access to drives, and photos loading directly into an app, bypassing the Camera roll! Revel in the ease of copying and pasting with new gestures! Bask in the glory of mouse usage via USB or Bluetooth in your desktop-class browser!
The strongest sign of iPadOS' significance, though, doesn't even exist within it. Rather, it lives in Project Catalyst, an initiative that will enable developers to create Mac apps from iOS apps, adding some of the desktop niceties in the course of a few days if early results prove typical. While iPhone-only apps will certainly jump to the Mac, the iPad is the natural starting point for such transitions given closer screen size similarities and more similar usage scenarios.
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With all these changes, Apple is changing the iPad -- once positioned as a subset-PC -- into a superset-PC. The platform that was dismissed as a "big iPod touch that nobody wants" is becoming something closer to the "touchscreen Mac that Apple won't make." Augmented reality is leading that charge today. But soon, as is becoming clearer, the Mac and iPad will have more in common than ever, as Apple follows Microsoft's lead and has MacOS running on ARM processors.
The iPad's advantages are platform versatility and modularity. But there's also a price range advantage. While Mac pricing begins at $799 for the Mac mini and will soon extend into the luxury car range with the new Mac Pro, iPads start at less than half of that price and feature the touch capabilities and app ecosystems that people increasingly take for granted. That said, if only your cold, dead hands will allow prying your Mac away from you, the Mac and iPad will work together better than ever.
Apple's commitment to the iPad leaves some nervous about the future of the Mac, with the thought that Project Catalyst will result in a dumbing down and lower level of optimization of apps for Apple's venerable computer. But it showed through in Apple's presentation that the company focuses extensively on optimizing its platforms. The Mac Pro, while a far cry from a mainstream device, shows how Apple is tenaciously fighting to keep the Mac attacking the height of demanding processing-intensive tasks well beyond an iPad's grasp. But if a tablet is to overtake the laptop, Apple wants to ensure that its logo graces that device's back.
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