Hello,
our app is in the App Store since August 18th 2015. It worked very well since then. But in the last couple of weeks, we got negative ratings in the App Store claiming the app is freezing. Moreover, the app seems to slow down the whole device once it froze. We couldn't reproduce the issue until the beginning of the year. Since then we experienced the same bahavior once in a while, while developing further features.
Detailed description:
While deploying the debug version from Xcode to a device, the app sporadically freezes at the launch screen. The debug log shows an appropriate start of the app and doesn't show any errors, exceptions or other suspicious output. What we can see is, that 'applicationDidEnterBackground:' is called before the app freezes. The app doesn't crash and the launch screen is displayed forever. The watchdog deamon doesn't kill the hanging process either. Furthermore the home button doesn't respond to inputs. The device can be recovered by killing the process with Xcode, then we see a black screen. After that, the home button can be pressed twice to remove the app from the recent apps.
Environment:
We experience these issues on iPhone 6 and iPhone 6s Plus with iOS 10.2.1 and 11.2.2 respectively. But we get user reports from various devices and iOS versions. We couldn't reproduce the issue on an iPhone 5 with iOS 9.3.5.
We currently use Xcode 9.2 for development.
Expected bahavior:
We'd expect either a crash with related log entries or the watchdog deamon to kill the hanging application.
I know this is not much info, but I hope anybody can help.
Kind regards
Peter