Bringing an era to a close, an upcoming version of iOS — possibly iOS 11 — will drop support for 32-bit apps entirely, according to an error message discovered in the first iOS 10.3 beta.
"This app will not work with future versions of iOS," the message warns when trying to load a 32-bit app in the beta, developer Peter Steinberger discovered. "The developer of this app needs to update it to improve its compatibility."
Apple has used 64-bit processors in iOS devices since 2013's iPhone 5s, and has been gradually ramping up pressure on developers to conform. New apps were required to offer 64-bit support in Feb. 2015, and that policy extended to app updates in June the same year.
The new message is an altered version of one present since iOS 9, simply warning that 32-bit apps might create slowdowns.
While iOS 10.3 is switching to a new filesystem, APFS, Apple is unlikely to drop 32-bit support in another point release, since it typically reserves any compatibility-breaking changes for its annual updates. iOS 11 should be announced at June's Worldwide Developers Conference and launch in September, if the company follows normal schedules.
A future switch to 64-bit only software will effectively cut off any support for any 32-bit based devices, such as the iPhone 5, iPhone 5c, and the fourth-generation iPad. Those products will be stuck without any iOS or app updates, and gradually become obsolete as Apple and developers move on.
Apple still hosts downloads of older software for equipment left behind by an architecture migration. For example, users of the original iPad that remains stuck on iOS 5 can still download PDF tool GoodReader that was compiled for the older OS.