On June 1, 2015, all apps in the App Store—new or existing—must support a 64-bit architecture or be nixed from Apple’s mobile marketplace.
Apple announced back in October that starting Feb. 1, 2015, all new App Store submissions must be built using the iOS 8 SDK with 64-bit support. This latest announcement, first reported by AppleInsider, gives developers about six months to make sure all existing apps are updated to support 64-bit architecture as well. As of June, all 32-bit applications will be barred from the App Store.
Apple recommended using the default “Standard architectures” build setting in the Xcode IDE to build a single binary interface with both 32-bit and 64-bit code.
Apple’s full mobile developer announcement is presented below: