This is a pre-release version of the complete Xcode developer toolset for Mac, iPhone, iPad, and Apple Watch. This release requires OS X Yosemite or OS X Mavericks.
Xcode 6.3 includes a new version of the Swift language. It includes a number of noteworthy changes to the language, detailed in the New in Xcode 6.3 beta section. Xcode 6.3 provides a migrator for moving your code to Swift 1.2. Swift has now reached 1.2 and includes a significantly enhanced compiler, as well as new features in the Swift language.
Xcode 6.3 Release notes
This release is a single application bundle. To install, double-click the downloaded DMG file, and drag the Xcode-beta.app file to your Applications folder.
From within Xcode, you launch additional developer tools, such as Instruments and FileMerge, via the Xcode > Open Developer Tool command. You can keep the additional tools in the Dock for direct access when Xcode is not running.
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