A root method has become available for the LG Optimus G running on Android 4.1.2 Jelly Bean.
The root file is shared by senior XDA developer Planet X. You can check out the development page to learn more.
Note that rooting your device will void your warranty. You can reclaim the warranty by unrooting the device later.
Disclaimer: iTech Post will not be held responsible for any damages to your device. All of the utilities in the guide belong to the owners or developers. Use at your own risk. Please also note that this guide is for the LG Optimus G running on Android 4.1.2 Jelly Bean. DO NOT try this on any other device.
Preparation:
1. Install USB driver for LG Optimus G.
2. Enable USB Debugging Mode on the phone to connect the computer with it and use Android SDK (Press Menu → Settings → Applications. Navigate to and click on the Development option to make sure that USB Debugging Mode is on).
3. BACK UP ALL DATA for your device. If the smartphone is having any custom recoveries like ClockworkMod/TWRP already installed, back up data using the recovery.
4. Your Optimus G should be at least 80 percent charged.
Directions:
1. Download root package for LG Optimus G to the computer (alternative link). The file name is motchopper.zip.
2. Extract the downloaded zip file into a single folder.
3. Connect your device to the computer using a USB cable (phone should be powered on).
4. Launch the Run.bat file.
5. A command prompt should pop up.
6. Follow the command prompt instructions.
7. Your device should soon be rooted.
To verify that your LG Optimus G has been rooted, download the Root Checker app from the Google Play Store. The SuperUse app should also be installed on your device.
