Mac Apps That Use Garbage Collection Must Move to ARC
February 20, 2015
Beginning May 1, 2015, new Mac apps and app updates submitted to the Mac App Store may no longer use garbage collection, which was deprecated in OS X Mountain Lion. Instead, migrate your apps to Automatic Reference Counting, using the migration assistant in Xcode to help with this transition. Apps may continue to use retain/release for manual memory management. For more information, read the Transitioning to ARC Release Notes.