If you installed OS X Yosemite at the end of last week then you've no doubt been busy exploring its various tools and features. Here are 17 new things you can do with the software, from hiding the traces of your Web browsing to recording screen activity on an iPad.

1. Search smarter

Spotlight isn't new, but it arrives with some new features: As with Spotlight on iOS, you can now search the Web and your iCloud locker as well as local files (use the Spotlight option in System Preferences to change this behavior). The Cmd+Spacebar keyboard shortcut will bring up Spotlight from anywhere.

2. Annotate emails

The Mail app included with Yosemite has a new Markup feature that you can use to annotate images and PDFs in your emails. Hover your cursor over any image in an email you're sending, then use the drop-down menu to the top right to activate Markup. You can then add text, lines and shapes on top.

3. Make phone calls

You can send texts and make calls from your Mac through your iPhone, as long as they're using the same iCloud account. From the Messages app on your Mac, open Preferences then the Accounts tab—make sure your phone number is ticked and selected in the Start new conversations from drop-down list.

4. Search with DuckDuckGo

As with the iOS 8 update, Safari in OS X Yosemite gives you the ability to set DuckDuckGo as your default search engine along with the other options like Google and Bing. DuckDuckGo's key feature is that it won't save the searches you're making or share your details with advertisers and other agencies.

5. Run the desktop Tumblr app

Tumblr has a new desktop app out for Mac, but it's only compatible with Yosemite. Install it for free from the App Store and you can blog, reblog and like away to your heart's content, though the Share extension is perhaps the most useful feature—it lets you share to Tumblr from any window in OS X.

6. Switch to a dark mode

If OS X Yosemite is a little too light and airy for your tastes, there's a new dark mode that you can activate to invert the entire interface. From System Preferences, open the General section and then tick Use dark menu bar and Dock. Not all third-party apps have dark mode support built in just yet.

7. Add widgets to the Notification Center

Another new feature previously seen on iOS 8, OS X Yosemite brings the Today view to the Notification Center and opens the floor to any third-party app extensions that want a piece of the action too. Wunderlist, 1Password, Pocket and Monity are some of the non-Apple apps that have already added support.

8. Handoff to other devices

Another major new feature is Handoff, the ability to start tasks on a computer then send them to a mobile device (or vice versa). You'll need to activate it on both your Mac and your iPhone/iPad, then a prompt appears whenever you're using a compatible app (like Mail or Safari). Lifehacker has a full guide.

9. Rename batches of files easily

Renaming a big group of files was possible in Mavericks, but it's easier in Yosemite. Drag a selection box over the relevant files in Finder, right-click and then choose the Rename option from the menu. You can use a find and replace approach, add a specified text string or create a new naming template.

10. Sign documents with your trackpad

Yosemite brings with it the ability to sign digital documents with your trackpad as well as a connected iSight camera. Load up a file in the Preview or Mail app and upon clicking the button to add a signature you'll notice there's a new Trackpad option. It's an even easier way of putting your name to something.

11. Add sound clips to messages

If you've been loving the new soundbite option in iOS 8's Messages tool, then there's some good news—it's turned up in Yosemite too, predictably enough. As on your mobile devices, click the microphone icon to record a snippet. If you want to keep your clips, be sure to export them out of the Messages app.

12. Record screen activity on an iOS device

Plug any iOS 8 device into your Mac using a Lightning cable and Yosemite lets you record screen activity quickly and easily. With the device connected, open the QuickTime Player app, choose File and New Movie Recording, then select your mobile device from the drop-down list next to the record button.

13. Take a 3D tour

Open up the Maps application in Yosemite and if you enter the name of a well-known city and jump to it, you'll see an option to start a 3D flyover tour. This is the same feature recently added to mobile devices with iOS 8 and new 3D cities have been added on a regular basis since the Yosemite beta began.

14. Connect to hotspots quickly

Start a hotspot from your iPhone (or cellular iPad), and it will instantly appear as an available network on your Mac—provided the mobile device is running iOS 8 and all of your hardware is signed into the same iCloud account. It's another of the features (like Handoff) under the umbrella of Continuity.

15. View open Safari tabs

Safari gets a bunch of new features with the upgrade to OS X Yosemite, one of which is the way in which open tabs are displayed. Click the new Show all tabs button in the top right corner to see a stacked series of thumbnails—if you have any private browsing tabs open, these will be grouped together.

16. Keep private windows separate

On a related note, private browsing tabs (where your activities and searches aren't logged by Safari) can be grouped together in one window while your standard tabs are kept in a different window. Just make sure you keep track of which is which (Safari turns the address bar dark while in private mode).

17. Delete some of your recent search history

One more from Safari: The browser now gives you more convenient control over which bits of your search history are deleted. From the Clear History and Website Data option on the History menu you can choose to obliterate results from the last hour, day or two days, rather than having to edit out results individually or erase everything at once.