64-bit Requirement for App Updates
April 8, 2015
As a reminder, beginning June 1, 2015 app updates submitted to the App Store must include 64-bit support and be built with the iOS 8 SDK. To enable 64-bit in your project, we recommend using the default Xcode build setting of “Standard architectures” to build a single binary with both 32-bit and 64-bit code. For more information, read the 64-Bit Transition Guide for Cocoa Touch.