When an app crashes on a device, the operating system creates a log of that event. The next time you connect the device to iTunes, iTunes downloads those records (known as crash logs) to your Mac. Ask testers of your app to send these crash logs to you along with any bug reports. Then view crash logs in the Devices and Simulators window.
Alternatively, if you use TestFlight or the App Store to distribute your app, Apple collects and aggregates crash logs into crash reports for you. You view these crash reports in the Crashes organizer.
Connect the device to a Mac running iTunes.
iTunes downloads the crash logs to your Mac.
In the Finder, choose Go > Go to Folder.
Enter ~/Library/Logs/CrashReporter/MobileDevice.
Open the folder identified by your device’s name.
Select the crash logs named after the app you’re testing.
Tip: To avoid sending duplicate crash logs to developers, delete the crash logs you previously sent.
In the Windows search field, enter the crash log directory for your operating system, replacing <user_name> with your Windows user name.
For crash log storage on Windows, type:
C:\Users\<user_name>\AppData\Roaming\Apple computer\Logs\CrashReporter/MobileDeviceFor crash log storage on Windows XP, type:
C:\Documents and Settings\<user_name>\Application Data\Apple computer\Logs\CrashReporterOpen the folder named after your device’s name.
Select the crash logs named after the app you’re testing.