You can submit 64-bit apps for iOS 7 today that take advantage of the power of iPhone 5s. Xcode can build your app with both 32-bit and 64-bit binaries included so it works across all devices running iOS 7. If you wish to continue to support iOS 6 then you will need to build for 32-bit only. Next month we will be making changes that will allow you to create a single app binary that supports 32-bit on iOS 6, as well as 32-bit and 64-bit on iOS 7. Learn more.

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Submitting 64-bit apps