Apple unveiled its upcoming new Mac operating system, OS X 10.10 Yosemite, during WWDC 2014 in June. Since then, Apple has opened up the beta of Yosemite to developers and one million members of the public for testing, but when will Yosemite officially come out? We explore release date rumours here, and bring you everything you need to know about Yosemite's price, spec and features. See also: iOS 8 review

Update: OS X Yosemite it in the Gold Master beta now which means that it could launch any day now!

OS X 10.10 Yosemite release date: When is Yosemite coming out?

It looks like Yosemite is almost ready to go, the golden master has just been made available to developers, and that usually means that the release is immanent.

The gold master version of Yosemite hit the Macs of those enrolled in the beta program at the same time as Microsoft was revealing Windows 10 – not Windows 9 as was expected, but a version of the Windows OS that sounds incredibly similar to Mac OS X (those in the know are aware that the X is the Roman numeral 10, not ex). Windows 10 won’t arrive until next year, by which point Apple might be considering moving to OS 11.

The latest version of Yosemite is likely to be as close to the final version as it is possible to be, although there may still be bugs.

While it is possible that Yosemite could roll out any day now, rumours are pointing to the 21 October as the day set aside for another Apple Event, this time it is rumoured that Apple will launch a new iPad Air, Mac mini, iMac with Retina display, and of course OS X Yosemite.

The beta version of Yosemite has been available to developers since June, while the public beta opened to the first one million people who registered on 25 July. They'll continue to test the beta version of Yosemite to help Apple iron out the bugs until its release this autumn.

So far, Apple has yet to be more specific than an autumn launch, but sources cited in a report from 9To5Mac claim that Yosemite will arrive in October.

The latest reports to emerge in September suggest a 21 October Apple event, during which Apple will unveil new iPads (presumably the iPad Air 2 and iPad mini 3) in addition to announcing the immediate availability of OS X Yosemite.

At time of writing, OS X Yosemite is in its third public beta and the eighth Developer Preview, so it shouldn't be long before the Gold Master version of the new operating system is released for testing ahead of the final public release.

In 2010, Apple announced OS X 10.7 Lion in October before releasing it to the public in July 2011. In February 2012, OS X 10.8 Mountain was announced before being rolled out in July 2012. Most recently, Apple announced OS X 10.9 Mavericks in June 2013 before making it available to the public in October 2013.

With OS X Mavericks not launching until October 2013, it seems likely that Apple will release its new Yosemite operating system in a similar time frame.

See: Will your Mac run Yosemite?

Apple will want to hurry the launch of Yosemite now that iOS 8 has arrived, because there are several features that won't work in iOS 8 until the new Mac OS is available, including iCloud Drive and Continuity.

Find out about the competition: read about how similar Windows 10 is to Mac OS X, and how Mac OS X Yosemite compares to Windows 8.

OS X 10.10 Yosemite: How to get the Yosemite beta

You can find out everything you need to know about getting the OS X Yosemite beta on your Mac here.

Before you install it, though, it's worth checking out our article on how to dual boot Yosemite and Mavericks on a Mac.

Despite download issues, it seems that the release of the public Yosemite beta doubled the adoption rate of the operating system within just 24 hours.

See also: 10 Mac OS X Yosemite tips and tricks

Read our 2014 Retina iMac release date rumours

OS X 10.10 Yosemite price: How much will Yosemite cost?

Apple surprised us last year by making OS X 10.9 Mavericks available for free. It is not so surprising to learn that Apple has confirmed that OS X Yosemite will also be free.

Previously, OS X Mountain Lion was just £13.99. 

See: OS X Yosemite FAQ

OS X 10.10 Yosemite: Design & new features

Apple's senior vide president of design Jonathan Ive and senior vice president of Software Engineering Craig Federighi have been working together on the redesign of Mac OS X in the run up to the launch of OS Yosemite. See: 22 Yosemite icons compared with their Mavericks counterparts

With Jony Ive's expanded design leadership reaching the software side of Apple, we c expected to see his influence prominently in the next Mac OS X and it looks like this is the case. The new operating system certainly has a new look. See also: 10 new features in Photos for iOS 8 and Mac OS X Yosemite

One of the biggest rumours was that OS X 10.10 would take a lot of cues from iOS for a more similar interface. During the WWDC keynote Apple made various references to Continuity, with new features for integration with the iPhone. In many ways the Mac can become an extension of your iPhone - you will even be able to take calls on it. See: Complete guide to Continuity

And yes, AirDrop will finally work between Mac and iOS!

iOS does appear to have adopted some of the more minimalist design that arrived oniPadiPhone and iPod touch in September. However, it still appears that Apple is still treating the two operating systems as completely separate entities but endeavouring to make the two work better together. 

There are also various improvements coming for Notification Centre, including a Today view, which gives you a quick look at everything you need to know. Notification Centre also gains Widgets, which it seems are no longer relegated to Dashboard. See also: Make OS X Notification Centre useful

iCloud Drive lives in the new look Finder and means that the documents you create on your Mac and iOS devices will be available on all your devices and in all your apps. It's Apple's answer to DropBox. See also: What's new in Calendar in iOS 8 and Mac OS X Yosemite.

Safari has a new streamlined design and a cleaner interface. The Tab View gives you an birds eye of your open tabs so it's easy to find what you are looking for. It's possible to set up a window for Private browsing, and when you search the results are no longer just limited to Google. See also: 12 great new Safari 8 features you might have missed

Mail has improvements for editing PDFs and images, and sending large attachments. See also: 10 new Messages features in Yosemite and iOS 8

Find out more in our OS X 10.10 Yosemite preview.

Find out how Yosemite compares to Windows in our comparison review.

OS X 10.10 Yosemite: Missing features

There are still some that have not yet been confirmed. Here are some features missing from Yosemite that we had hoped to see.

Read: The best OS X Yosemite features we can't wait for

Siri for the Mac 

Many expected Apple to make Siri available on the Mac in OS X 10.9. Apple's voice technology was introduced more than two years ago on the iPhone 4S, and then on the iPad, but has yet to make its way onto the Mac. See also: Siri for Mac rumour round-up

Control Centre

We were hoping Apple will decide to bring iOS 7's Control Centre to OS X 10.10. It could revolutionise System Preferences and make them more accessible for the less experienced user.

New features in Yosemite

You can read all about the new features in Yosemite over in our Yosemite Topic Zone. Including the following: