When an app crashes or uses excessive CPU on a device, the operating system creates a log of that event. The next time you connect the device to your Mac, the system downloads those records (known as crash or energy logs) to your Mac. Ask testers of your app to send these logs to you along with any bug reports. Then view the logs you import from other sources in the Devices and Simulators window.
Alternatively, if you use TestFlight or the App Store to distribute your app, Apple collects and aggregates logs into crash and energy reports for you. You view crash and energy reports in the organizer.
Connect the device to your Mac.
The system downloads the 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 logs named after the app you’re testing.
Tip: To avoid sending duplicate logs to developers, delete the logs you previously sent.
In the Windows search field, enter the 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 logs named after the app you’re testing.