Apple Stops Signing iOS 13.3.1 Following Release of iOS 13.4

IPSWFollowing the release of iOS 13.4 on March 24, Apple has stopped signing iOS 13.3.1, which means downgrading to that version of iOS is no longer possible.

iOS 13.3.1 was a minor update that added a toggle for disabling the U1 chip in Apple's iPhone 11, 11 Pro, and 11 Pro Max.

Apple routinely stops signing older versions of software updates after new releases come out in order to encourage customers to keep their operating systems up to date.

iOS 13.4 is the current publicly available version of iOS, with the update bringing a new Mail toolbar, iCloud Folder Sharing, new Memoji stickers, trackpad support on iPad, and more.

Developers can also download iOS 13.4.5, an upcoming update with bug fixes and a new option to share Apple Music songs on Instagram Stories.

Popular Stories

iPhone 17 Pro Iridescent Feature 2

iPhone 17 Pro Clear Case Leak Reveals Three Key Changes

Sunday August 31, 2025 1:26 pm PDT by
Apple is expected to unveil the iPhone 17 series on Tuesday, September 9, and last-minute rumors about the devices continue to surface. The latest info comes from a leaker known as Majin Bu, who has shared alleged images of Apple's Clear Case for the iPhone 17 Pro and Pro Max, or at least replicas. Image Credit: @MajinBuOfficial The images show three alleged changes compared to Apple's iP...
iPhone 17 Pro Dark Blue and Orange

iPhone 17 Release Date, Pre-Orders, and What to Expect

Thursday August 28, 2025 4:08 am PDT by
An iPhone 17 announcement is a dead cert for September 2025 – Apple has already sent out invites for an "Awe dropping" event on Tuesday, September 9 at the Apple Park campus in Cupertino, California. The timing follows Apple's trend of introducing new iPhone models annually in the fall. At the event, Apple is expected to unveil its new-generation iPhone 17, an all-new ultra-thin iPhone 17...
iphone 16 pro ghost hand

iPhone 17 Pro: 5 Reasons Not to Upgrade This Year

Monday September 1, 2025 4:35 am PDT by
Apple will launch its new iPhone 17 series this month, and the iPhone 17 Pro models are expected to get a new design for the rear casing and the camera area. But more significant changes to the lineup are not expected until next year, when the iPhone 18 models arrive. If you're thinking of trading in your iPhone for this year's latest, consider the following features rumored to be coming to...
xiaomi apple ad india

Apple and Samsung Push Back Against Xiaomi's Bold India Ads

Friday August 29, 2025 4:54 am PDT by
Apple and Samsung have reportedly issued cease-and-desist notices to Xiaomi in India for an ad campaign that directly compares the rivals' devices to Xiaomi's products. The two companies have threatened the Chinese vendor with legal action, calling the ads "disparaging." Ads have appeared in local print media and on social media that take pot shots at the competitors' premium offerings. One...
iOS 18 on iPhone Arrow Down

Apple Preparing iOS 18.7 for iPhones as iOS 26 Release Date Nears

Sunday August 31, 2025 4:35 pm PDT by
Apple is preparing to release iOS 18.7 for compatible iPhone models, according to evidence of the update in the MacRumors visitor logs. We expect iOS 18.7 to be released in September, alongside iOS 26. The update will likely include fixes for security vulnerabilities, but little else. iOS 18.7 will be one of the final updates ever released for the iPhone XS, iPhone XS Max, and iPhone XR,...
iPhone eSIM Feature

Apple Hints at iPhone 17 Models Lacking SIM Card Slot in More Countries

Sunday August 31, 2025 8:52 am PDT by
Another hint has surfaced that Apple is preparing to eliminate the physical SIM card tray from iPhones in more countries this year. In particular, a source familiar with the matter has informed MacRumors that retail employees at Apple Authorized Resellers in the EU are required to complete a training course related to iPhones with eSIM support by Friday, September 5. There are 27 countries...

Top Rated Comments

JosephAW Avatar
71 months ago
Still happily on iOS 12.4.1. Every time I think of upgrading I read all kinds of horror stories with email and crashing and the such. Maybe iOS 14 will be better. Not likely though. I think each iteration is progressively getting worse. iOS 8 was my favorite then iOS 10.
Score: 4 Votes (Like | Disagree)
calzon65 Avatar
71 months ago
I have always hated Apple's pathetic "no downgrade" policy. There are countless stories of people upgrading then discovering weeks later the upgrade broke something. I don't care what Apple's reasons are, this is and has been a terrible policy for consumers. :mad:
Score: 4 Votes (Like | Disagree)
MattMJB0188 Avatar
71 months ago
They stopped signing 13.3.1 and I'm still on 12.4 lol. I get much better performance on my 8 Plus than 13.4.
Score: 4 Votes (Like | Disagree)
Pakaku Avatar
71 months ago
The fact that Apple refuses to let people downgrade their iOS versions will always be one of the many reasons I can never consider iOS devices to be "real" computers
Score: 3 Votes (Like | Disagree)
Villarrealadrian Avatar
71 months ago
This should be illegal...
Score: 2 Votes (Like | Disagree)
mdorais Avatar
71 months ago

I have always hated Apple's pathetic "no downgrade" policy. There are countless stories of people upgrading then discovering weeks later the upgrade broke something. I don't care what Apple's reasons are, this is and has been a terrible policy for consumers. :mad:
Agreed. They broke playing homemade mp4's so now I can't watch them anymore on my iPad. Only Apple purchased movies work now. Wish I could down downgrade because I gained nothing useful but lost a major function by upgrading.
Score: 1 Votes (Like | Disagree)