I have posted some updates on our issues getting ExpoKit apps to work on iOS 13 here Anybody else have problems with iOS 13 using the ExpoKit instructions? (UPDATE: not fixed) - #4 by llamaluvr and submitted an issue here fishhook.c EXEC_BAD_ACCESS error when running ExpoKit/ managed workflow apps on iOS 13.1 device · Issue #5532 · expo/expo · GitHub.
I just wanted to cross-post here because we just confirmed we get a similar-looking (can’t see actual errors b/c it’s prod) crash on our managed workflow app. Looking at Expo’s RN forks, while they do have. the “__unused signature changed” error fixed, the fishhook.c fix ([Xcode 11] [iOS 13] EXC_BAD_ACCESS in fishhook.c · Issue #25182 · facebook/react-native · GitHub) does not appear to have been cherry-picked. We are only seeing this issue on an iOS 13 beta device (in our case, an iPad mini 5th gen), and are not seeing it on any iOS simulators.