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 APIs 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.
To obtain your copy of this new release, get a redemption code from the Mac Dev Center. Then proceed to the Mac App Store to redeem your code and download the fourth developer preview of Mac OS X Lion. To build apps with this version of Lion you must use Xcode 4.1 Developer Preview 6 available from the Mac Dev Center.