OS X Mavericks adds new features and capabilities to everything from the apps you use every day to the technologies that power your Mac.
Complete control of the Mac with a single button for people with impaired physical and motor skills.
Automatically scan through and access keys on the keyboard. Built-in features such as predictive text and Sticky Keys help improve typing efficiency.
Use a sweeping cursor to simulate mouse movements such as moving around the screen, clicking, and dragging.
Switch Control highlights elements of the active window of the current application, including search fields and controls such as scroll bars and buttons (does not apply in web content).
Menu bar access
Scan sequentially across items in the menu bar. Once you select the one you want, click to drill down into menus, and then click again to select individual commands and options or navigate submenus.
Cycle through applications in the Dock to launch apps or bring an app to the front
Third-party device support
Switch Control works with a variety of popular USB and Bluetooth enabled switch hardware that can generate mouse buttons, joystick buttons, and select key presses. Supports return, space, tab, escape, backspace, left arrow, right arrow, down arrow, up arrow, and F1 F15. Other keys will not be recognized.
Switch Control makes it easy to navigate and operate basic controls such as volume, brightness, eject, and media playback.
Switch Control Panel Editor
Create, edit, and share your own onscreen keyboards to streamline commonly used actions and shortcuts for different applications. With the Switch Control Panel Editor, you can position groups of buttons together; customize color, text, size, and imagery, and specify the layout. Once you have created the perfect keyboard for a specific app or task, sharing it with others is easy. The files can be emailed and opened directly into the Panel Editor for review and import.
VoiceOver image analysis
Help tags of images will give a brief image description.
Custom Switch Control settings
With Switch Control settings, you can control elements such as the speed at which the cursor scans through items, actions assigned to connected switch devices, and the computer’s sensitivity to unintentional switch clicks.
Customize closed captions
Users can select the appearance of closed captions, including fonts, highlights, and backgrounds. These settings will apply in apps such as iTunes and QuickTime Player.
Multilingual voice support
Certain voices can now read multiple languages that occur in the same paragraph.
VoiceOver can now speak MathML equations on the web.
Voice-Over can now duck the system sound when speaking.
Fast character echo
Performance of character typing echo has been improved.
Calendar has a new look and includes new month and week views that make it easy to spot the current day and week.
Streamlined event inspector
The redesigned inspector makes it easy to see your event details and simplifies editing.
Type an address or place in the location field and Calendar looks up the address to verify and autocomplete it. Calendar even offers suggestions based on the information you enter.
Calendar can automatically calculate driving or walking travel time to your next event. You can even have it alert you when it’s time to leave.
See an inline map of your event location in the inspector. When you click the map, the Maps app opens with directions to the event.
The inspector includes a weather forecast for your upcoming event so you know what to wear.
When friends invite you to events on Facebook, the invitations appear in Calendar.
Regional holiday calendars
Holiday calendars are built into Calendar and automatically appear based on your region and language.
Email all attendees
Quickly send an email to all the event attendees by choosing “Email attendees” from the contextual menu.
Send a message to all attendees
Send an iMessage to the attendees right from the contextual menu.
Scroll smoothly through your calendar in month and week views. As you scroll, months and weeks follow your gesture so you can focus on specific periods of time, like the last two weeks of one month and the first two weeks of the next.
Automatic Mobile Device Management enrollment of organization-owned devices
It’s easier to configure and manage Mac systems by automatically enrolling your Mac into your organization’s Mobile Device Management MDM system during setup.
FileVault recovery key, key rotation, key escrow management
Mobile Device Management systems can now be used to report on the status of FileVault activation and the use of personal and institutional recovery keys. They can also give administrators the ability to remotely change recovery keys.
More advanced passcode policies
Administrators can require more advanced security policies to impose maximum age and avoid passcode reuse.
Scripts and workflows can send notifications to alert the user of important information.
AppleScript Editor and Automator support Documents in the Cloud so you can access your scripts, applets, and workflows from all of your Mac computers.
Automator workflows can be saved as Speakable Items so they can be executed as a voice command when Speakable Items is activated in Accessibility preferences
The “Use” clause imports the terminology and functionality of AppleScript Libraries and scriptable applications through a simple single-line declaration placed at the top of a script, such as “use application ‘Finder’,” or “use ‘My AppleScript Text Library’.”
Applets and droplets can now be signed with a Developer ID.
AppleScript Libraries provide a new plug-in architecture for extending the power and capabilities of AppleScript. AppleScript Libraries are user-created script files and bundles — written using AppleScript or AppleScript Objective-C — that can be referenced in scripts to provide specialized handlers and functionality.
Contacts features an elegant new look that minimizes distraction and makes it easy to find the contact information you’re looking for.
Click the Show Map button next to an address to see it in the Maps app.
Improved photo picker
You can choose from Facebook, Twitter, and LinkedIn profile photos for your contact card and your friends’ cards.
Improved Google contacts support
Add a Google account to Contacts and your Google contacts instantly appear. When you edit a Google contact, the information is immediately updated on both your Mac and Google. You can also view your Google contacts in a separate group in Contacts.
Adding address information for a card is even easier. When you paste an address into Contacts, you can paste part of the address in one field and Contacts automatically adds the rest of the information to the appropriate fields.
With Enhanced Dictation, you can use dictation even when you don’t have an Internet connection. Choose Enhanced Dictation in Dictation preferences to download the voice recognition engine.
When you use Enhanced Dictation, there’s no time limit on how long you can talk. Just turn on Dictation and start talking.
With Enhanced Dictation, your words appear onscreen as you talk, so you can see exactly what you’ve entered without having to pause
App Nap regulates applications you’re not using so they consume less energy. When an app is open but not visible — say it’s hidden behind another window, or you’re using a different app in full screen App Nap conserves battery life by slowing the app down.
When your system’s memory begins to fill up, Compressed Memory automatically compresses the least recently used items in memory. When these items are needed again, they can be uncompressed in an instant.
Timer Coalescing intelligently groups low-level operations — which can occur tens of thousands of times every second — to create tiny periods of idle time that allow your CPU to enter a low-power state more often. The result is that the CPU uses less energy while giving your battery a break.
SMB2 is the new default protocol for sharing files between two Mac computers running OS X Mavericks. SMB2 is faster, increases security, and improves Windows compatibility.
Application Layer VPN
Application Layer VPN allows applications to individually establish secure virtual private network connections to remote services.
Expanded OpenCL support
OpenCL in OS X Mavericks supports Intel HD Graphics 4000, Intel HD Graphics 5000, and Intel Iris Pro integrated graphics processors, letting apps tap into the parallel computing power of even more Mac systems.
The iBooks Store is built into the app and features more than 2 million books. View featured books from the iBooks Store or the New York Times best-seller lists, or browse by author or genre. When you purchase a book, it downloads to your Mac ready to read.
See all your books
All the books you have downloaded on your iPad, iPhone, and iPod touch will automatically appear on your Mac so you can browse and read them from all of your devices. You can even organize them into collections.
iCloud keeps your current page up to date everywhere, as well as highlights, notes, bookmarks, and collections. So you can pick up right where you left off, regardless of the device you used last.
Navigate using gestures
Swipe the trackpad or mouse to flip through pages in the book.
Choose from three themes White, Sepia, and Night which make it easy to read in any environment.
Choose from a selection of stunning fonts and adjust the text size for comfortable reading.
Highlight important sections of text. You can even choose your highlight color.
Add notes to any text selection. Switch to the Notes Panel to see all your notes and highlights instantly organized in one place.
Use the built-in Study Cards to review your most important notes and highlights.
Immerse yourself in your favorite book by reading in full screen.
Find a word, character, or phrase anywhere in your book with the powerful search feature.
With iBooks for Mac, you can keep as many books open as you like. You can even open the same book in multiple windows so you can refer to different passages at the same time.
Share directly from the page to Facebook or Twitter. You can also send a snippet via text or email.
If a book you purchased is republished with new or additional content, iBooks lets you know. You can download the update for free, and it automatically replaces the older copy on your bookshelf.
Experience gorgeous, full-screen Multi‑Touch books designed just for iBooks. They’re filled with interactive features, diagrams, photos, videos, and more.
In addition to keeping all your books in one place, iBooks organizes your PDF files. Double-click a PDF to open it in your favorite PDF reader on the Mac.
iBooks makes it a snap to cite passages from a book. When you copy text from the book to use as a quotation in a Pages document, a citation is automatically created.
Look up definitions
Look up definitions for words in English, German, Spanish, French, Japanese, Dutch, Italian, and Simplified Chinese.
Restrict access to the iBooks Store as well as the ability to read books with explicit content.
Finder Tabs make it easier than ever to manage files in the Finder . With tabs, you can consolidate all your Finder windows into one.
Merge all windows
To consolidate your Finder windows into a single window with tabs, go to the Window menu and choose Merge All Windows.
Drag to create a window
Create a new Finder window by dragging a tab out.
Custom view per tab
For each tab, you can select the view that’s most helpful to you. Keep one tab in icon view, for example, and another in list, column, or Cover Flow view.
Drag to reorder
Drag tabs left or right to put them exactly where you want them.
Spring-loaded drag and drop
Easily move or copy a file from one location to another. Drag and hold a file on a tab and it will spring open so you can drop the file into any subfolder in another tab.
You can tag a file from the Finder. Just select the file and click the new Tag button in the toolbar.
Sort by tag
The Finder includes the option to sort by tag so you can easily find the files you’re looking for.
You can now use the Finder as a full-screen app and easily access all your folders with Finder Tabs. When you take the Finder full screen, it moves to its own space. You can swipe back and forth between the Finder and your other apps.
Drag to resize columns
In list view, you can resize a column by dragging the edge until it’s exactly the right size.
Sign in to LinkedIn once in System Preferences and OS X sets up LinkedIn for Contacts, Notification Center, Safari Shared Links, and Sharing.
LinkedIn connections in Contacts
See your LinkedIn connections in Contacts. When you use LinkedIn single sign-on, the Contacts app displays your connections’ LinkedIn profile pictures and information.
Receive a notification when someone sends you a message or an invitation to connect. Clicking a notification takes you to the LinkedIn website, where you can choose which notifications you want to receive in Notification Center.
View Shared Links in Safari
Links shared by your connections and by influencers you follow on LinkedIn appear in Shared Links. Safari shows you who shared the link and provides a text preview of the web page. Click a link to open it, or click a profile photo in Shared Links to see the person’s profile page on LinkedIn.
Click the Update Profile Photos button to add a LinkedIn picture for people who are already in your contacts.
LinkedIn Share sheet
Easily share links and updates with your professional network. When you use LinkedIn single sign-on, LinkedIn appears as a Share menu option in Safari and in Notification Center. LinkedIn Share sheets let you specify whether the update is visible to anyone or just to your connections.
Encrypted storage and transmission
Information is protected with robust 256-bit AES encryption. Your information is always encrypted on all your devices, in transit, and in the cloud.
When you enable iCloud Keychain on a second device, you’ll receive a notification requesting approval on your original device. Once you approve it, iCloud Keychain pushes your encrypted information to the additional device.
Safari automatically fills in your user name and password on the sites you choose with iCloud Keychain. Just click the login button to access the site. iCloud Keychain makes your web passwords available across all the Mac computers and iOS devices you approve.
Easy credit card entry
For speedy online checkout, iCloud Keychain can safely store and fill in your credit card number when you make a purchase from a website. iCloud Keychain makes your credit card numbers and expiration dates available across all of the Mac computers and iOS devices you approve.
Safari can suggest passworws that mix letters and numbers in hard-to-guess combinations. You don’t need to remember them, because iCloud Keychain pushes the passwords to your devices and autofills them when you want to log in.
Automatic account setup
iCloud can now push the accounts you use in Mail, Contacts , Calendar, and Messages to each of your Mac computers. If you’re signed in to Facebook, Twitter, LinkedIn, or other accounts in Internet Accounts in OS X, iCloud can push them to each Mac as well.
If you use only one device or happen to lose all your devices, you can restore your entire Keychain.
Advanced security settings
iCloud Keychain includes advanced settings that allow you to choose an iCloud security code longer than four digits or have iCloud Keychain generate one for for you. You can also choose to disable recovery so the keychain is kept up to date on all devices but the encrypted data is not stored with Apple and cannot be recovered if all the devices are lost.
Mail in OS X Mavericks improves scrolling performance, allowing you to quickly browse through your inbox or a long conversation.
Faster message display
When you click a message in your inbox, it displays even faster in OS X Mavericks.
Faster message download
Downloading messages from Gmail and Exchange is now even faster.
View maps inline
Mail makes it easy to map addresses and locations right from a message. If you want directions or more details about an address, you can view the address in the Maps app.
Move Gmail messages from your inbox and save them to the All Mail folder with a single click.
Mac App Store
If an update requires a restart, or if an app can’t be updated because it is running, you’ll receive a notification that lets you choose when to apply the update. If you choose Try Tonight, the update wil l be installed between 2 a.m. and 5 a.m. When you return to your Mac in the morning, you’ll find it just as you left it.
Auto-install app updates
The Mac App Store can update your apps automatically. If you opt in to automatic updates, your apps update in the background when they’re not running. A notification informs you that apps have been updated. This option can be turned off in the App Store pane in System Preferences.
You can download multiple apps at the same time.
In-app purchase subscriptions
Developers of periodicals can take advantage of support for in-app subscriptions. Users can now subscribe to updating content within an app, as well as review and manage their subscriptions from their personal account page.
Update apps purchased from all accounts
Easily keep apps up to date, even on a shared Mac. Clicking Update All in the Mac App Store updates all the apps purchased by all the accounts on your Mac.
The Mac App Store launches even faster and checks for software updates faster. Scrolling through a page of apps is faster and smoother, too.
Easy iMessage setup
Messages makes it easier than ever to set up your accounts. Just type in your Apple ID and password to get started with iMessage. You can also easily add other chat service accounts the first time you launch Messages.
New emoji browser
For faster access to emoji, click the smiley in the reply field and Messages presents several hundred emoji organized by theme. Just click one to add it to your message.
Send messages to Contacts groups
Quickly send a message to everyone in a group you set up in Contacts. Type in the name of the group, and Messages adds all the people.
Send to iPhone
Plan your trip on your Mac and send directions or a location to your iPhone, where they appear as a notification. On your iPhone, you can use voice navigation to guide you while you’re on the road.
Maps makes getting there simple. Just enter a location or an address and Maps provides detailed directions and alternate routes.
Interactive vector maps
Maps uses a vector-based engine that keeps text crisp and clear. Panning and zooming are smooth and responsive at any resolution.
View select major cities from the air with photo-realistic, interactive 3D views. Explore each city in high resolution as you zoom, pan, tilt, and rotate around it and its landmarks.
Easily find restaurants, stores, and other places of interest. Information cards display addresses, phone numbers, and even Yelp ratings, reviews, and photos.
Search for a location
Use the search field to find locations around the world by simply typing in the city.
Navigate with gestures
Pan, zoom, and rotate maps using the Multi‑Touch trackpad on your Mac.
Maps uses real-time traffic information to calculate your ETA. It gives you details on traffic backups, so you can tell if there’s a major incident or just a temporary slowdown. And if traffic is a mess, Maps offers alternate routes to save you time.
Share a map
The built-in Share button makes it simple to send directions to your iOS devices or to share them using Mail, Messages, or social networks like Facebook and Twitter.
Persistent info cards
You can drag information cards to your desktop to keep them handy.
Export as PDF
Create a PDF of any map so you can take it with you and have it available offline.
You can print a map with directions so you have a copy of it on the go. The printout includes a beautifully formatted map and point-to-point directions.
Maps are integrated in OS X apps. Mail, Messages, and Calendar automatically detect addresses and can display them in inline maps. Clicking an inline map opens the location in the Maps app.
Bookmark locations and routes so your favorite places are just a click away.
Bookmarks and recent searches are pushed to all your devices via iCloud so you can search for places on your Mac and have them available on your iPhone, iPad, or iPod touch when you’re on the road.
With Maps in OS X you can have multiple windows open at the same time, so you can view two or more locations simultaneously.
Take advantage of every pixel on your Mac by using Maps in full screen.
When you receive a Messages notification, click it to send a response right from the notification.
Notifications from Mail include a reply and delete button so you can act on them without leaving the app you are in.
FaceTime replies and reminders
Incoming FaceTime calls appear as notifications. Just click to accept the call. If you need to decline, you can instantly reply with an iMessage or set a callback reminder right from the notification.
The Mac App Store can automatically update your apps, and it sends you a notification when an app has been updated. If the update requires a restart, or if an app can’t be updated because it’s running, you’ll receive a notification that lets you choose when to apply the update.
Notifications from websites
Websites can send notifications to keep you up to date. Once you choose to receive a website’s notifications, they appear seamlessly as OS X notifications, even when Safari isn’t running. You can configure your notifications on a per-website basis in the Notifications pane of System Preferences.
Do Not Disturb
Use Do Not Disturb to disable notifications on your Mac. In the Notifications pane of System Preferences, you can specify exactly when you want to turn it on.
You can choose to hide the preview text in a notification.
System alerts with updates about your battery, Time Machine backups, and ejected disks appear as notifications, so you can easily spot them with the rest of your notifications.
Send a message from Notification Center
Notification Center includes a Messages Share sheet so you can quickly send an iMessage from anywhere in OS X.
While you were away
Quickly see what happened while you were away. Your Mac continues to receive notifications while sleeping, so you always have the latest information. When you open your Mac, a summary of the notifications you missed will appear on the Lock screen.
View notifications on Lock screen
Notifications can appear onscreen even if your display is asleep or screen lock is on.
Set snooze time for events and reminders
When a Calendar notification appears for an upcoming event, you can choose how long to snooze it by clicking and holding the Snooze button on the notification. You can also snooze reminders from a notification.
Desktop with menu bar and Dock
Each display connected to your Mac has a desktop with its own menu bar, so there’s nothing to configure. The Dock is available when you move your cursor to the bottom of the screen, letting you easily access menus and apps from anywhere.
Full-screen apps on each display
You can use full-screen apps on each display connected to your Mac. Swipe on the trackpad or mouse to switch between full-screen apps.
Multidisplay Mission Control
OS X Mavericks makes it easy to manage the apps running on each display. Mission Control shows you everything that’s on each display, including windows on the desktop and full-screen apps. If you want to move an app from one display to another, simply drag its thumbnail to the desired display.
With AirPlay Display and Apple TV, you can use your HDTV as a second display.
More sorting options
Now you can sort your reminders by due date, priority, and creation date.
Sort order pushed to iCloud
When you manually reorder items in a list, the changes are pushed to iCloud so you have the same order on all your devices.
Reminders automatically creates a Today reminder list that displays the reminders due that day, along with overdue reminders.
Restore your completed reminders so that you can reuse a list like a grocery list without reentering the same items.
You can now choose the font, alignment, and size of text annotations right from the Edit toolbar. Use copy and paste to quickly duplicate an existing annotation or even copy it to a different document. New alignment guides help you position annotations on a PDF page or image.
Redesigned bookmarks make it easy to return to interesting pages in a PDF document. You can place bookmarks in a file and quickly navigate to them using the bookmarks list in the sidebar. You can even see your bookmarks as you scroll through a document.
You can now highlight and point to areas on the screen while you walk another user through an issue.
Use Multi‑Touch gestures
You can tap, scroll, pinch, and swipe on your trackpad to control a remote Mac in a more fluid, natural, and intuitive way.
Shared Links shows you links from people you follow on Twitter and from your LinkedIn connections. You can see who shared the link as well as the comments they posted about it. Signing in to Twitter and LinkedIn in the Internet Accounts pane of System Preferences sets up Shared Links.
See profile photos
Shared links shows the current profile photo for people you follow on Twitter and LinkedIn. Click the person’s photo to go to his or her profile page on the Twitter or LinkedIn website.
A search field at the top of the sidebar makes it easy to find web pages in your bookmarks and Reading List by page title. In Shared Links, you can search for text in comments, or for posts by a specific person just type his or her name in the field.
A Retweet button in Shared Links lets you easily retweet links from people you follow on Twitter.
When you’re catching up on your Reading List or Shared Links, all your articles scroll from one to the next as if you were on one continuous web page.
The Safari Sidebar makes it easy to access your bookmarks, Reading list, and Shared Links. Just click the Bookmarks icon in the Favorites Bar to open the sidebar.
With energy-saving features like Safari Power Saver and App Nap, Safari is the most energy-efficient browser.
Thanks to advanced memory management, the new process-per-page architecture works without taking a heavy toll on your system’s memory. Safari and the rest of your system stay responsive — even when you’re multitasking.
Safari is smart about plug-ins, so you don’t waste power playing plug-in content when it’s not the focus of your browsing. When web pages you visit contain plug-ins in their margins, Safari displays a preview of the plug-in content but waits until you click it before running it.
Redesigned Top Sites
Top Sites has a fresh new look. It’s also easier to customize — just drag and drop web page thumbnails where you want them.
Process per web page
Each web page runs in a separate process, making the browser more stable and responsive, even when you have many tabs and windows open. With separate processes for each web page, an unresponsive web process won’t affect your other tabs or windows, allowing you to keep browsing without reloading pages or restarting Safari.
When you use the Smart Search Field to navigate to a web page, Safari preloads the Top Hit in the background so it‘s available even faster if you choose it.
iCloud Tabs autocomplete
When you type in the Smart Search Field, Safari shows you web pages in your iCloud Tabs, making it easy to pick up your browsing where you left off on another device.
Leading Russian search provider Yandex is a built-in option for Russian users, in addition to Google, Yahoo!, and Bing.
Third-party data blocking
In addition to blocking cookies, Safari offers even more privacy protection by preventing third-party websites from leaving other types of data — such as plug-in, cache, and local storage data — that could be used to track you online.
Kerning and ligature support
Text in web pages automatically benefits from support for kerning and ligatures in Safari.
Saving your favorite sites is even easier in Safari. Just click the + button to the left of the Smart Search Field to add your current web page to Reading List, or click and hold to choose bookmarks.
When you see an address on a web page, highlight it and Control-click to see a map inline. Click the map to open the Maps app.
Easily return a file to the person who sent it. Files that you receive have a Share menu option to return the file to the sender, so you can open an email attachment, edit it, and send it back with just a few clicks.
Share videos to Facebook
Share videos to Facebook using Share sheets. The Share button now lets you post videos to Facebook from the Finder and Quick Look.
Photo Booth profile photos
You can set your Facebook and LinkedIn profile photos right from Photo Booth.
More sandboxed apps
Sandboxing extends to more apps, including the Mac App Store, Messages, Calendar, Contacts, Photo Booth, Dictionary, and Font Book.
Adobe Flash Player, Silverlight, QuickTime, and Oracle Java plug-ins are sandboxed in Safari.
FIPS 140-2 certification
OS X Mavericks is in the process of receiving FIPS (Federal Information Processing Standard Publication) 140-2 validation. This government certification process evaluates the cryptographic implementation and algorithms used in OS X against a set of rigorous standards.
Fast certificate response
Apple can now act even faster to protect users if certificates on their system have been compromised. Apple can deliver over-the-air updates that disable exploited certificates without requiring users to apply a software update.
Easy document tagging
You can tag a file from the Save dialog, the Finder, or the iCloud Document Library. When you click in the Tags field, choose from your recent tags or type in a new one.
Files can have multiple tags, giving you the flexibility to organize files across multiple projects.
Tags in Finder sidebar
Your tags automatically appear in the Finder sidebar, so it’s easy to find tagged files no matter where they’re located.
Search by tag
Quickly find files by tag. Simply enter the name or color of the tag in the Finder search field and it creates a token for that tag. You can even combine multiple tags.
You can create Favorite tags that are always accessible from the contextual menu, making it easy to quickly tag a file.
Tags you have used recently are always available in the Tag popover and the Finder sidebar.
Drag to tag
Drag files to the Tag section of the Finder sideba r to tag them.
You can assign a color to a tag to make it more recognizable in the Finder.
As you type in the Tags field, you’ll see matching suggestions from your existing tags.
Pushed to iCloud
Tags are pushed to iCloud, so you can access tags you created from any of your Mac computers. Just start typing in the Tags field and suggestions from your existing tags appear, no matter which Mac you’re using. Tags appear in the same order in the Finder sidebar across your computers.
The dictionary app in OS X Mavericks includes the following new definition dictionaries: Dutch, Italian, and Korean. Dictionary also includes new Simplified Chinese to English and Korean to English dictionaries.
Export as PDF menu item
A new Export as PDF option in the File menu of many system apps lets you create a PDF and even add it to the Preview iCloud library.
OS X includes new fonts for Arabic and Chinese users.
New Data Detectors languages
Data Detectors supports Croatian, Slovak, Romanian, Ukrainian, Greek, Czech, Hungarian, and Thai, so it can recognize phone numbers, addresses, and dates in those languages.
New apps highlighted in Launchpad
When you purchase a new app or update an existing app from the Mac App Store, its icon sparkles the first time you open Launchpad, making it easy to find.
Increased Power Nap support
iMac (Late 2012 and newer), Mac Pro (Late 2013), and Mac mini (Late 2012) now support Power Nap, so they stay up to date while they sleep.
Energy use in Activity Monitor
Keep track of how much energy your apps are using. Activity Monitor includes a new Power tab that displays all the apps currently running and shows how many watts they are using.
Memory stats in Activity Monitor
The Memory tab in Activity Monitor has been redesigned making it easier to track the memory usage of your Mac. View stats such as app memory, file cache, and Compressed Memory, as well as a graph displaying current memory pressure.
Power information in Battery menu
The Battery menu item on Mac notebooks can tell you if an app is consuming a significant amount of power. Click the Battery menu to see a list of apps.
OS X Mavericks is localized in Malay, Vietnamese, and Indonesian.
Developer tools on demand
OS X Mavericks automatically installs command-line tools, compilers, and framework packages the first time you need them, and keeps them updated automatically.