October 12, 2011, 10:08 AM — It seems like every time a major software revision comes along, it's described as the "biggest ever." In the case of iOS 5, though, that might not be hyperbole—there's hardly a part of Apple's mobile operating system that isn't altered in some way by the latest update.
Don't think that this is just change for change's sake, however. By and large, iOS 5's changes are for the better, spackling a number of shortcomings and gaps in functionality that have existed since day one.
Tempting as it may be to dub iOS 5 the "Snow Leopard" of iOS, though, it's clear there's a lot more to this than simply filling gaps. iOS 5 marks the first major revision of iOS to be simultaneously released for the iPhone, iPod touch, and iPad. It also finally brings feature parity between the CDMA (Verizon) and GSM (AT&T) versions of the iPhone. In fact, all of Apple's iOS devices are on the same page now (with the exception of the few specific features—such as Siri voice-control—that are limited to the iPhone 4S).
And that page isn't exactly what you think it is, either. With iOS 5, Apple's theory of the post-PC era finally moves into practice. No longer are iOS devices second-class citizens, tethered to the sinking anchor of a personal computer. With iOS 5, it's possible, for the first time, to use your iPhone, iPod touch, or iPad as your one and only device.
PC Free, with every purchase
Despite touting the PC-free capability on its list of features at this year's Worldwide Developers Conference, the ability to use your iOS device sans PC isn't really one feature, but a collection of them. That said, it represents perhaps the most important shift ever in thinking about Apple's non-PC devices.
Going back to the original iPod, Apple's non-PC devices have been viewed as accessories. You bought an iPod to go with your computer. Your iPhone synced data with your computer. Your Apple TV streamed content from your computer. By the time Apple released the iPad, that concept was straining at the seams. After all, what is the iPad if not a computing device in its own right? Why does it need to be subservient to a Mac or PC?
As of iOS 5, your iPhone, iPod touch, or iPad can stand in the place where it lives, with no need for a Mac or PC to prop it up. The importance of this change is impossible to ignore. A year and a half ago, I argued that the iPad heralded a third revolution, but where that was a warning shot—a promise of things to come—iOS 5 finally delivers on that promise.