Apple sent out a notification to developers today, giving them a heads up on a few upcoming changes to its App Store submission policy. Posted in its developer portal, the bulletin says that beginning in February of next year, iOS applications must meet two new requirements.
Starting February 1, 2015, new apps and updates must be built using the iOS 8 SDK (software development kit), and they must include 64-bit support, otherwise they will be rejected. Apple made a similar announcement around this time last year for iOS 7 app optimization.