Apple Stops Signing iOS 17.3.1, Downgrading No Longer Available
Apple today stopped signing iOS 17.3.1 preventing iPhone users from downgrading to that version of iOS. iOS 17.3.1 is no longer being signed following the March 5 release of iOS 17.4, an update that introduced app ecosystem changes in the EU, new emoji, and more.

Apple routinely stops signing older versions of iOS, so it is not unusual that the iOS 17.3.1 update is no longer available. Apple prevents users from installing older versions of iOS to encourage customers to keep their operating systems up to date and to prevent downgrading to older, less secure versions of the iPhone operating system.
iOS 17.4 is now the only publicly released version of iOS available.
Popular Stories
Apple is about to release iOS 27, which will finally deliver more advanced Siri AI capabilities as well as a variety of other refinements, improvements, and new features to iPhones. It's Apple's biggest software update of the year, and Apple announced at Wednesday's iPhone event that it will be releasing iOS 27 sometime tomorrow – Monday, September 14.
iOS 27 won't be the only release on...
T-Mobile will charge customers $5 per month to use iPhone Handoff, an e-SIM feature that allows the same phone number to be used on two separate iPhones.
iPhone Handoff requires carrier support, and at launch, only T-Mobile users in the U.S. and Deutsche Telekom users in Germany will be able to use it.
T-Mobile says customers can use their number across two compatible iPhone models and...
As noted by Nicolas Lellouche, who writes for the French tech website Numerama, Apple has updated its tech specs pages for the iPhone 18 Pro and iPhone 18 Pro Max to clarify which models are equipped with its new C2 cellular modem and where.
Apple now says the iPhone 18 Pro has a C2 modem worldwide, while the iPhone 18 Pro Max uses the chip in every country except for the U.S.
According...