View real-time log of iOS (iPhone, iPad, iPodTouch)

Two ways to do so.

1. From Xcode

The solution documented by Apple in Technical Q&A QA1747 Debugging Deployed iOS Apps for Xcode 6 is:

1. Choose Window -> Devices from the Xcode menu.
2. Choose the device in the left column.
3. Click the up-triangle at the bottom left of the right hand panel to show the device console.

2. By idevicesyslog

Connect your device, open up Terminal.app and type:

idevicesyslog

Up 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 log messages from a particular app:

idevicesyslog | grep myappname

1. ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
   
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3. Once run, follow the prompts to complete the installation. Once homebrew is installed, run the following brew command to download the required components and then libimobiledevice:
   
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5. brew install -v --devel --fresh automake autoconf libtool wget libimobiledevice
   
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7. Then run ideviceinstaller:
   
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9. brew install -v --HEAD --fresh --build-from-source ideviceinstaller
   
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11. Once these are installed, you can plug in a paired device, unlock it and use the following command to view the logs on the screen:
    
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13. idevicesyslog
    
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15. This is akin to running a tail against the device. Again, the device must be paired. You can use the command line (e.g. if you’re running this on Linux) to view the logs, but if you’re not paired you’ll need to use idevicepair to pair your device, followed by the pair verb (which is very different from the pear verb):
    
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17. idevicepair pair
    
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19. You can also unpair using the unpair verb:
    
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21. idevicepair unpair