For Real devices

  1. Open Settings app
  2. Tap Privacy
  3. Tap Analytics & Improvements
  4. Tap Analytics Data
  5. There might be quite a lot of Data, so try to pinpoint the possible one using date:


6. Tap the Share button at the top right corner, you can share it with Airdrop or any other way you prefer

For Simulators

If you are using simulators, things will even be much easier, those logs will be in the following path:

/Users/[your user name]/Library/Logs/CoreSimulator

Then you will find there are some folders like this:

Dir like 4B43D000-AD34-4535-8E0B-C556525315B9 are your simulator id, which you can find from Xcode -> Window → Devices and Simulators:

Get into that directory, and you will the output file is under system.log and crashes under CrashReporter (if you have any).

Reference