Apple provides a service that collects logs from users for apps that you distribute using TestFlight or distribute through the App Store. The service organizes the logs for the past two weeks into downloadable crash and energy reports. The service does the following:
Collects logs from apps and app extensions running on user devices
Symbolicates the logs (replaces memory addresses with human-readable names)
Compares stack traces to identify and group similar logs into reports
Removes all personal user data from logs
Provides the total number of unique devices where the event occurred
Provides a sample set of logs for each report
Updates reports daily
For energy reports, a log is generated when an app exceeds a reasonable CPU threshold in the foreground or background, and causes excessive battery usage. Each log is a sampling of the CPU over several minutes.
You view crash reports in the Crashes organizer and energy reports in the Energy organizer. To open the organizer, choose Window > Organizer, then click either Crashes or Energy.