Many apps are broken in iPadOS 17.7.7 due to NSUserDefaults
Since we updated an iPad (6th generation) to iPadOS 17.7.7 yesterday (May 12, 2025), we have found that many apps, including apps we previously released as an App Store developer, are broken to various degrees. The apps seem to forget their states, such as configuration parameters and login credentials. These problems did not exist in iPadOS 17.7.6 before. Neither do they exist on other models of iPhones and iPads running earlier versions of iOS and iPadOS we use for testing.
Circumstantial evidences point to iPadOS 17.7.7 itself as the culprit. In order to dig out more evidence, we used Xcode 16.2 to debug our own apps, which like many other apps, use NSUserDefaults (or UserDefaults in Swift) as a convenient way to store small pieces of persistent data, such as user preferences and app settings. For example,
NSUserDefaults *usrDefaults = [NSUserDefaults standardUserDefaults];
It turns out that the value returned for any key of usrDefaults is nil. That explains why our apps forget many of their setting parameters. What a bummer!
Let's hope that Apple will release a quick fix (in iPadOS 17.7.8) ASAP. In the meanwhile, don't upgrade to iOS 17.7.7 if you haven't.
iPad (6th generation)
