The devices which were bought from Google Play is takju. and From Samsung is Yakju.
I think your phone is Yakju(Google Play didn't sell Devices in india).
Takju gets All Upadte Directly from Google.
If you want to get all update from Google at the time of release you have to convert to Takju.
How Can you do that
Please follow below to convert from yakju to takju (stock) without loosing your data/apps: (assuming you know adb & fastboot and have set them up on your computer. Also assuming that bootloader is unlocked) [Please read before you implement]
- Download the 4.2 factory images for Takju from http://goo.gl/UMbmS
- Extract files using 7-zip on Windows (you need to extract twice and will get the files as: bootloader-xxx.img; radio-xxx.img and image-xxx.zip)
- Copy these files to the location android-sdk/platform-tools/ (if you have the android-sdk installed or to the location where adb & fastboot is)
- Plug in your Galaxy Nexus (ensure Debug option is enabled under Developer Settings
- Follow these commands:
a. adb reboot bootloader
b. fastboot flash bootloader bootloader-xxx.img
c. fastboot reboot-bootloader
d. fastboot flash radio radio-xxx.img
e. fastboot reboot-bootloader
f. fastboot update image-xxx.zip
This would update your Galaxy Nexus from Stock 4.1.2 (yakju) to Stock 4.2 (takju) without losing any data/apps
1. If you using Windows follow the video tutorial to setup adb and fastboot http://goo.gl/jGcic
2. If you are on Mac, use ./ before the commands for execution
Note 2: With this method you don't need to remove the userdata.img as the command "fastboot update image-xxx.zip" does not touch the userdata on your device.
*Disclaimer: Tried with Unlocked Bootloader, but you follow these at your own risk.
Or you can Download factory image for yakju from here and try similar step above for just upadating(with out converting from Yakju to takju)