There is lots of analysis out on the web now about how important the 64-bit-ness of Apple’s new A7 chip (in the iPhone 5S). They all seem to be missing a big point: the A7’s power means all sorts of desktop application power can be used on iOS devices like the iPhone 5S, and the soon-to-be-announced iPad 5 (I imagine the iPad mini 2 will use a last-generation processor, such as the iPad 4’s A6X, to keep its price down).

Let’s take a look at Apple’s iWork suite (now free for new iOS device purchasers, by the way) for an example of what the future might look like for OS X and iOS apps.

Pages (word processor), Keynote (presentations), and Numbers (spreadsheet) comprise the iWork suite. Right now there’s a creaky old desktop (OS X) version from 2009 and an iOS version that has a significant number of features from the desktop version, but is not feature complete. (Despite the desktop version being old, it has been upgraded with new features over time, such as iCloud syncing.) So the iOS versions of iWork apps are somewhat less fully featured than the desktop versions, but they have a touch-optimized interface that makes them very easy to use on iPhones and iPads.

Web versions of the iWork apps are now in beta at iCloud.com. Interestingly, they don’t look exactly like either the desktop or mobile versions, although they all share similarities.

So, there are some pain points right now, with each version being slightly different. The biggest one is the conversion process that has to happen when you load a document saved in the desktop version to iCloud, and you want to edit it on an iPhone or iPad. Because the desktop and mobile version don’t have the same feature set, their file formats are different, and a file conversion has to happen. This is usually seamless, but there can be hiccups.

Keep in mind that the iOS versions have to be hobbled, somewhat, because they are compatible with devices running iOS 5. That includes the original iPad, which had a scant 256 MB of RAM (compared to probably 2GB in the iPhone 5S and iPad 5), and used an A4 chip (compared to the A7 chip just announced). In a way, it’s surprising that Apple got so much of the desktop iWork suite functionality to run on such processor- and RAM-limited devices.

But now it’s 2013, and the iPhone 5S and iPad 5 will run with an A7 chip. Apple calls the 64-bit A7 “desktop class”. Look at the performance increase over older chips:

So, if you have this kind of power, why would you develop a hobbled mobile-specific app? Wouldn’t you create a completely feature complete app that worked identically on mobile devices as it does on the desktop? And if you could do that, wouldn’t you create a common data file format that would work across all devices and sync seamlessly through iCloud, rather than have to go through conversions?

“Desktop class apps on an iPhone? How absurd!,” you say. Well, you’re not going to write a Ph.D. dissertation on your iPhone, granted. But what, really, is the difference between an 11″ MacBook Air and a 9.7″ iPad? Not much more than 1 inch. So why hobble an iPad app anymore if it’s using a desktop class chip, and it’s screen is virtually the same size as a laptop?

Remember that, under the covers, iOS and OS X are built on the same foundation. If they’re now built on the same 64-bit foundation, that makes creating iOS and OS X compatible apps almost easy. The big difference is the UI. (I’ll talk about that in a future post.)

So, does a 64-bit chip mean anything dramatic for the iPhone 5S. Sort of. But its real significance will come with the iPad 5, and what that means for the power of iOS apps in general.

iWork (and iLife) are due for a major overhaul. This will either happen with the introduction of the iPad 5 or the launch of OS X Mavericks and new Macs. In other words, some time this fall. My expectation is that, at least on A7-powered devices, the iOS and OS X apps will be feature-identical.

This is monumental. As you think about your “mobile” strategy for your enterprise, you need to start wondering about what “mobile” really is. Is it a cut-down feature set, or is it just a touch-based interface that’s flexible enough to work on phones and tablets? With the advent of the 64 bit A7, it’s looking a lot more like the latter than the former.