iOS iphone will log in terminal output

For the emulator, its log file at the terminal is located at: ~/library/logs/coresimulator/c4b94ba6-ef08-4ad2-ae7d-1a3a2e2ac545/system.log

For real machines:

Here's another tip using the Great Libimobiledevice library http://www.libimobiledevice.org/, originally built to Mana GE IOS devices on Linux. This method shows your can view the log output (e.g. what do I see in Xcode if running in debug mode) on a NY app, whether it's an appstore build or a adhoc build. Some Apps is more talkative than others-it all depends on what careful the developers were to remove log messages in Release builds. I Find this is useful for debugging issues in release versions of our apps. If a user reports a sequence of actions causes a crash, you can try this out while watching the log from your app.
Here's how:

• Grab the Libimobiledevice binary for Mac OS X from my github account athttps://github.com/benvium/libimobiledevice-macosx/ Zipball/master
• Follow the install instructions here:
  Https://github.com/benvium/libimobiledevice-macosx/blob/master/README.md

Connect your device, Open up Terminal.app and type: IdevicesyslogUp pops a real-time display of the device ' s system log.

With it being a console app, you can filter the log using UNIX commands, such as grep


For instance, see all logs messages from a particular app:

Idevicesyslog | grep myappname

iOS iphone will log in terminal output