Apple's new Mac operating system, OS X 10.10 Yosemite, arrived in October and is believed to be running on one in five Macs. Here's everything you need to know about Mac OS X 10.10 Yosemite's features, system requirements, bugs and updates, as well as its features and how to upgrade your Mac to OS X Yosemite and more.

Apple announced that Yosemite would be available to download following its 16 October keynote where it also unveiled a Retina iMac, a new Mac mini, the iPad Air 2 and the iPad mini 3. It actually didn't arrive until a few hours later, much to many Mac users' frustration. It turned out that this was the first of many frustrations for users of Yosemite. 

If you haven't yet updated to Yosemite you can do so by clicking the Upgrade Now button on Apple's site.

But should you upgrade? In this article we look at some of the issues with Yosemite, including problems with WiFi in Yosemite, difficulties getting Apple's new Continuity features (AirDrop, HandOff and phone calls made on the Mac) to work. We also look at updates to Yosemite including 10.10.1.

Read next: Yosemite pros and cons

Plus read: Yosemite tips for beginners

Watch our Yosemite tips video:

OS X 10.10 Yosemite: WiFi issues, 10.10.1 & 10.10.2 updates, and how to install Yosemite updates with no WiFi

The discussion forums on Apple's support site continue to accumulate large numbers of messages from users who say that their WiFi connections haven't worked reliably since they upgraded to OS X Yosemite.

Reports of connectivity issues cropped up within hours of Apple releasing Yosemite on 16 October, and have continued to pour in since.

Some users have had success implementing one or more of the seemingly endless suggestions that have piled up on the thread, others on Apple's support site and on third-party blogs. Turning Bluetooth off on nearby Macs and iOS devices has worked for some, for example, but not all. Others reported having WiFi connectivity problems with OS X Mavericks as well, but that conditions sharply deteriorated once Yosemite had been installed.

Like many others, we have experienced Wi-Fi connection failures and slow speeds since updating to Yosemite. Initially blaming the router, but that made no sense as our iPhone and iPad had no problems with the WiFi network. We eventually became aware that a number of people were experiencing difficulties, and it was quickly recognised that Yosemite was to blame.

Apple has been trying to address these WiFi issues. The company seeded the beta of 10.10.1 to developers on 4 November, asking developers to look at changes to WiFi. Yosemite 10.10.1 was also to include changes to the Notification Centre.

The 10.10.1 update to Yosemite was finally issued on 17 November. As expected, it was supposed to cure WiFi problems that many people had been experiencing since installing Yosemite.  Apple even said: “Improves WiFi reliability” in the notes accompanying the release. When we initially installed the update it seemed to improve our Wi-Fi connection but this was unfortunately short lived.

Installing the update on our MacBook Air wasn't easy. Because the MacBook Air has no ethernet port we had no means to plug it into network without an adapter, which we don't own - a Thunderbolt to Gigabit Ethernet Adaptor costs £25, as does a USB Ethernet Adaptor. With no WiFi connection downloading the Yosemite update was going to be a challenge, and then we didn’t know for sure that it would do the trick - even when we were trying to download it we were aware of forum posts suggesting that the update didn't cure everyone’s Yosemite induced WiFi problems.

However, we decided that it was worth a try (we needed to be able to get online as we were working from home that day). We're lucky that we are able to create a hotspot from our mobile, plus we don’t have major limits on data on my contract, so we were able to create a WiFi network from the phone and use that to download the Yosemite update over 4G.

It’s 329MB of data, so if you don’t have data to spare this may not be the best option for you. The download took less than 5 minutes, and we were able to install the software update and boot up our Mac again pretty quickly. Here’s how to create a WiFi hotspot from your iPhone.

Initially after installing the update our WiFi seemed to be ok. But over the days that followed it slipped back to it's sluggish or non existent self.

We weren't the only ones to continue to experience problems with WiFi in Yosemite 10.10.1. Affected users have continued to post complaints in Apple's discussion forums, third-party sites and on social media. One thread in the Apple Support site, titled "OSX Yosemite WiFi issues," has more than 1,420 comments and has been viewed almost 294,960 times since Yosemite first came out on 16 October.

If you are still having WiFi problems, 9to5 Mac points to an Apple Forum that suggests going to System Preferences > Network > Advanced and removing old entries from the preferred network list, as well as performing an SMC reset.

iMore has published an article detailing what it calls a "possible fix" for the WiFi issues in Yosemite, suggesting that modifying the Network system preferences to prevent them from slipping onto another WiFi network.

Apple appears to have reacted to the fact that WiFi issues are persisting in Yosemite with the release of another beta to testers. Build 10.10.2 (14C68k) was released on 24 November.

Read our review of OS X Server (Yosemite) and our review of Yosemite.

OS X 10.10 Yosemite: How to get OS X Yosemite

If you haven't installed Yosemite yet, and the lack of WiFi stories above don't put you off, and you are the owner of a sufficiently powerful Mac, you can upgrade for free.

Go to Apple's site, and find the Yosemite page. Here's a direct link. Scroll down a touch and click the blue Upgrade Now button. Follow the instructions in the Mac App Store.

Your Mac will need 2GB of RAM to run Yosemite, and 8GB of available storage. You'll also need to be currently running OS X 10.6.8 Snow Leopard or later, because you'll need the Mac App Store to download the update.

Yosemite will run on the following Macs:

  • iMac (Mid-2007 or later)
  • MacBook (13-inch Aluminum, Late 2008), (13-inch, Early 2009 or later)
  • MacBook Pro (13-inch, Mid-2009 or later), (15-inch, Mid/Late 2007 or later), (17-inch, Late 2007 or later)
  • MacBook Air (Late 2008 or later)
  • Mac Mini (Early 2009 or later)
  • Mac Pro (Early 2008 or later)
  • Xserve (Early 2009)

The system requirements for Yosemite are the same as those for OS X 10.9 Mavericks, the current operating system for Mac.

As of 3 November, Yosemite was powering about one in five Macs, an update rate that surpassed last year's Mavericks in first-month adoption speed, analytics company Net Applications has said, so accounts of Yosemite problems do not seem to have had a major impact on the OS's update.

Mac OS X Yosemite UK price: How much does Yosemite cost?

Apple surprised us last year by making OS X 10.9 Mavericks available for free. This year we were prepared for the news - and sure enough, OS X Yosemite is also free.

(If you're interested, Mac OS X Mountain Lion, the OS before Mavericks, was just £13.99, so Apple isn't leaving all that much money on the table.)

Mac OS X Yosemite: Design & new features

Apple's senior vice 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 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 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 lauch event 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 finally works between Mac and iOS!

iOS does appear to have adopted some of the more minimalist design language that arrived on iPadiPhone and iPod touch last year. 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 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: Mail in Yosemite and 10 new Messages features in Yosemite

And find out how Yosemite compares to Windows in our comparison review.

For more discussion of Yosemite's new features, here's a video where we poke around the beta:

New features in Yosemite

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

Head over to page two to read what we wrote ahead of the launch of OS X Yosemite, including rumours about features, design and more.