Download OS X Lion
Mac Developer Program members can download Mac OS X Lion Developer Preview now. Start developing your apps today so they’re ready for the Mac App Store when Lion ships this summer.
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The eighth major release of the world's most advanced operating system challenges the accepted way of doing things by introducing new features that change the way you use a computer. This developer preview features over 3,000 new API's covering a range of new technologies and capabilities that you can incorporate into your apps. Start developing your apps today so they are ready when Lion ships this summer.
Mac App Store
OS X Lion includes the Mac App Store — the best place for users to discover, purchase, and download your apps. Millions of customers in over 90 countries can quickly and easily select from some of the best Mac apps conveniently on their Mac. You can also enhance the user experience and capabilities of the Lion apps you offer on the Mac App Store with:
In-App Purchase
In-App Purchase allows you to offer your customers additional digital content, functionality, and services within your paid app. The Store Kit framework provides the functionality to process payments via iTunes. And like the business terms for apps sold on the App Store, you'll receive 70% of the purchase price for each item you sell within your app.
Push Notifications
The Apple Push Notification service allows you to notify your users of important information or updates even when your app isn't running. Push Notifications can be used in a wide variety of apps. For example, if you are designing a sports app, you can notify users of key game updates. If your app manages tasks, you can show the number of tasks a user has to complete. A badge will appear on your app icon or on launchpad, letting a user know there's a notification waiting for them.
Learn more about the Mac App Store
Full Screen Apps
Provide an immersive, focused user experience with a full screen app. NSApplication, NSWindow, and the NSWindowDelegate Protocol in OS X Lion make it easy for you to create and manage full-screen user interfaces while providing you the power to design rich user interactions.
Multi-Touch Gestures and Animations
Multi-Touch gestures transform the way you interact with your Mac, making all you do more intuitive and direct. Now an even richer Multi-Touch experience comes to OS X Lion. Enjoy more fluid and realistic gesture responses, including rubber-band scrolling, page and image zoom, and full-screen swiping.
AV Foundation
AV Foundation framework provides essential services for working with time-based audiovisual media. Through an Objective-C interface, you can easily play, examine and compose audiovisual media in your app. An array of powerful classes also make it simple to edit and encode media files. You can even capture audio and video from external devices and manipulate them in realtime.
Auto Save and Versions
If you have a document-based application, Lion offers an efficient, built-in auto save feature that stores changes to the working document instead of creating additional copies on a disk. Versions automatically records a history of changes made to your documents and lets your app display a Time Machine like interface so users can browse through previous versions.
Resume
Now apps you close will reopen right where you left off, so you never have to start from scratch again. And when you install software updates, you no longer need to save your work, close your apps, and spend valuable time setting everything up again. With Resume, you can restart your Mac and return to what you were doing with all your apps in the exact places you left them.
Aqua
Aqua defines the look and feel that users come to expect from OS X. Lion enhances this experience with popovers and overlay scrollbars.
Popovers
AppKit framework now includes popovers, a new unit of content that can be positioned relative to other content on the screen. Popovers automatically move whenever the positioning view moves. You can also design popovers that can be detached, allowing them to become a separate window.
Overlay Scrollbars
OS X Lion introduces overlay scrollbars similar to those in iOS. These scrollbars appear as an overlay on top of the window's content while the user is scrolling and remain visible briefly to allow scrollbar dragging.
Sandboxing and Privilege Separation
Create apps that are more secure with app sandboxing and privilege separation. Sandboxing protects the system by limiting the kinds of things an application can do, such as accessing files on disk or resources over the network. Limiting the capabilities of an app to just those operations that it needs to perform helps keep the rest of the system more secure in the event that an app is compromised. Privilege separation is another common technique for improving security where an app is factored into smaller pieces, each with their own distinct roles and privileges.
iCloud and File Coordination APIs
iCloud Storage APIs let your application send documents and key value data to a central location, where a user can then access them from all of their computers and iOS devices without having to sync or transfer files explicitly. Storing documents in a user's iCloud account also provides a layer of security. Even if a user loses a device, the documents on that device are not lost if they are in iCloud Storage. The file coordination APIs are part of document storage, providing a mechanism that 'locks' documents so multiple instances of your application don't attempt to write the same data to the user's iCloud Storage.
Learn more about iCloud
