Apple will this year release two operating systemsiOS 6 for iPhone, iPad and iPod touch, and Apple OS X 10.8 Mountain Lion for Macs and MacBooks. But what's the difference between iOS 6 and Mountain Lion? We explain.

Many more clever tech industry watchers than me were taken aback by the very existence of OS X 10.8 Mountain Lion. The removal of the word 'Mac' from the last but one iteration of OS X seemed symptomatic of an operating system that was moving ever closer to its little iOS brother and into a brave new Post-PC world. The suggestion was that iOS would swallow up OS X, in a single unified operating system, much in the same way that Microsoft is attempting to roll up every device into Windows 8.

That it hasn't happen is in some ways testament to the enduring brilliance of OS X. Like so many of Apple's key products, OS X wasn't the first of its kind, but it is probably the best from a consumer point of view. There were graphical X86 PC operating systems before OS X, but none has been so stable and easy to use, for so long.

Here we'll take a look at the new features in both iOS 6 and OS X 10.8 Mountain Lion, and then look at the way features found in both work differently. See also: How to use iMessage in OS X 10.8 Mountain Lion.

iOS 6 vs Mountain Lion: comparing the new features

iOS 6 iOS 6 will launch in late September, and brings with it a bevvy of new and interesting features. Chief among these is the removal of Google Maps, to be replaced by Apple's own Maps, with Yelp integration and real-time crowdsourced traffic information. Well, expect those in the US, at least, Yelp isn't nearly as useful on this side of the pond. You will get turn-by-turn navigation by default, however, and this will fold in traffic information to update your route on the fly. And Maps themselves will be a lot prettier, we are told. For a start they are rendered in 3D, and there is also a top-down satellite view.

The Phone app has been shown some much-needed love. Do Not Disturb mode is clever, letting you put the phone on silent and blank out the screen, unless the same number calls you repeatedly - an emergency situation, perhaps. You'll also be able, for instance, to dismiss incoming calls with pre-loaded messages such as "I'm busy and will call back later" (and then automatically set a reminder to ensure you do exactly that).

There have been improvements to Siri, the intelligent iOS voice-recognition function. Siri is coming to the iPad, and now supports auto integration. In principle at least Siri has better integration with apps and online services, and should in turn have greater knowledge. Again, it remains to be seen how well that will pan out away from the States.

As Microsoft is attempting with Windows 8, Apple is integrating social networking  notifications into iOS, and appending Facebook info into Contacts. The same thing is happening with OS X 10.8 Mountain Lion - you get built-in Facebook support so that Mac users can easily share photos and status updates, and add Facebook contacts to their contacts book. In both operating systems the Notification Center will shows Facebook updates.

OS X 10.8 Mountain Lion

Similarly you'll be able match up Apple IDs and phone numbers, so just as Mountain Lion users can now call and iMessage other Mac users over the web, iOS device users will be able to join in. The difference is that iOS users will be able to make voice and FaceTime calls over 3G.

Finally in iOS, expect a new VIP Mailbox, that will push new emails to the lock screen in the same way that iOS 5 posts social network updates and SMS messages.

OS X enjoys other new features in Mountain Lion. For Mac completists AirPlay mirroring lets you share your computer's screen with an Apple TV. For those whose Macs contain SSDs there's a feature known as 'Power nap' that lets you put your PC to sleep as it performs OS updates, updates App Store apps, and backs up.

The Mac now gets the Game Center, so you can play games with and against other Mac and iOS users. There are other new apps too, including Messages, Notes, and Reminders, as well as Dictation. Those of you who are awake will notice that these are all very iOS-like applications.

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