Hi, I have trouble finding a crash during app startup when the phone is not attached to Xcode. The problem does not show up when the app/iphone is attached to xcode nor running on simulator. The app will run correctly for first few days on the phone, then the app starts to crash at startup (launch screen comes up and app shuts down). The app read data from a JSon file and populates UI with previously stored settings from userDefaults. All data are written to userDefaults immediately when changed and validated before writing to userDefaults. I rigorously check the data retrieved from JSon and userDefaults to make sure they are not corrupted and not out of bound. All optional variables are checked against nil before use. The issue disappears once I have attached the phone to xcode and tried to debug it, or reinstall the app.
Additionally, I also checked to see if there is any crash log stored on the phone. None are associated with my app nor any DayOne logs.
Could someone show me a way or tools that can trace this issue?
Xcode 10.0 (10A254a)
iphone 8 w/ 11.4.1
