Xcode is a complete developer toolset for creating apps for Mac, iPhone, iPad and Apple Watch. Xcode brings user interface design, coding, testing, debugging, and submitting to the App Store all into a unified workflow.
Downloading and Updating Xcode and SDKs
The current release of Xcode is available as a free download from the Mac App Store. The Mac App Store will notify you when an update is available or you can have OS X update automatically as it becomes available.
The latest beta versions of Xcode can be downloaded from the Xcode download page. Previous versions of Xcode can also be downloaded here. To download beta or previous versions of Xcode, simply sign in with your Apple ID. Program membership is not required.
Providing Feedback and Reporting Bugs
Your feedback goes a long way towards making Xcode even better. With Apple Bug Reporter, you can report issues or request enhancements to APIs and tools. Include detailed information about issues, including the system and developer tools version information, and any relevant crash logs or console messages.To provide feedback or ask questions, post your questions and comments on the Apple Developer Forums.
Submitting Apps to the App Store using Xcode
If you're an Apple Developer Program member, Xcode provides an integrated workflow to prepare and submit apps to App Store. You should use the latest version of Xcode available on the Mac App Store to submit your apps, or when available, the latest GM seed release from the Xcode download page. For more information, read the App Distribution Guide.
Do not submit apps built using beta software, as beta versions of Xcode, Operating Systems, and SDKs are for development and testing only.
Invalid Private Key and Certificate Pairing
If you received an error message saying, "Xcode could not find a valid private-key/certificate pair for this profile in your keychain." This error message indicates that the Keychain Access application on your Mac is missing either the public or private key for the certificate you are using to sign your app.
This often happens when you are trying to sign and build your app from a different Mac than the one you originally used to request your code signing certificate. It can also happen if your certificate has expired or has been revoked. Ensure that your app's provisioning profile contains a valid code signing certificate, and that the Keychain Access application on your Mac contains that certificate, the private key originally used to generate that certificate, and the WWDR Intermediate Certificate.
For instructions on how to resolve this and other code signing erros, review the Code Signing Support page.
The Apple developer website contains a wealth of documentation, videos, and community-based information to help you develop with Apple technologies using Xcode.
Apple Security Updates
For information on the security content of Xcode updates, visit the Apple security updates page.