Like Verizon, like Sprint. Both carriers are bound to take their own sweet time before updating their Galaxy Nexus variants to Android 4.2 while unlocked Galaxy Nexus owners enjoy the latest iteration of Android. The Verizon Galaxy Nexus saw a custom Android 4.2 ROM come out, giving users a way to try out 4.2 and all its features without waiting for the official update, and now a similar custom Android 4.2 ROM has come out for the Sprint variant.

XDA forum member iwasaperson has used the Android 4.2 sources and put together a stock Android 4.2 ROM, hacked to work with the Sprint Galaxy Nexus. It hasn’t been touched in any way and is fully stock Android 4.2, getting you all its new features, including a new keyboard, lockscreen widgets, improved Google Now, Photo Sphere camera, and more.

However, to try out the ROM, you will need an unlocked bootloader on your Galaxy Nexus. While there is a simple procedure for unlocking the bootloader, keep in mind that it will erase all data on your phone, including everything on the SD card, so you will need to backup and restore important things later on. Also, due to a change in the location of the sdcard partition in 4.2, some apps’ data may not restore correctly.

Let’s take a look at how the custom Android 4.2 ROM can be installed on the Sprint Galaxy Nexus.

Compatibility

The procedure described below is only for the Sprint Galaxy Nexus. Do not try it on any other device.

Warning!

The methods and procedures discussed here are considered risky and you should not attempt anything if you don’t know completely what it is. If any damage occurs to your device, we won’t be held liable.

How to Install Custom Android 4.2 ROM on Sprint Galaxy Nexus

  1. The procedure to flash this ROM involves unlocking the bootloader on the device, which causes all the data on the device to get wiped, including everything on your internal storage. So, backup installed apps and other data such as contacts, messages, bookmarks, etc, by referring to our Android Backup Guide for help. Then, copy everything from the SD card to your computer, which will also include the apps and data you backed up.
  2. You will need your phone’s bootloader unlocked. Follow the guide → here (external link) to unlock the bootloader. Make sure you took a backup in step 1 as this will wipe all data from the phone and reset it to factory settings. Skip this if you already have the bootloader unlocked.
  3. Make sure you have ClockworkMod recovery installed on the phone. If not, use this guide to do so.
  4. Download the latest version of the ROM from the source page.
  5. Download the Google Apps package. This will install apps like Play Store, Gmail, etc. which are not present in the ROM by default.
    Download Gapps | Filename: GoogleAppsPack-4.2.0-JOP40C.zip
  6. Copy both the ROM and the Gapps file to the phone. Remember, do not extract the files, copy them to the device without extracting.
  7. Boot into ClockworkMod (CWM) recovery. To do this, turn off the phone. Then, press and hold the following keys together: Power + Volume Up + Volume Down to enter Fastboot mode where you will see “Start” written in big green letters. Then, using the volume buttons, navigate to the Recovery mode option, then select it using the Power button to reboot into recovery mode.
  8. Perform a Nandroid Backup of your existing ROM, so that you can always restore it from recovery if something does not work out with this ROM (this will backup the entire firmware on the phone). To perform a backup, select Backup and Restore –> On the next screen, select Backup again. Go back to main recovery menu after backup is complete.
  9. Select wipe data/factory reset, then select Yes on next screen to confirm. Wait a while till the data wipe is complete (this will only wipe installed apps and settings, but will not wipe files on the SD card).
  10. Select install zip from sdcard, then select choose zip from sdcard. Scroll to the ROM file and select it. Confirm installation on the next screen.
  11. After ROM installation completes, select choose zip from sdcard again, then select the GoogleAppsPack-4.2.0-JOP40C.zip file to install the Google apps package.
  12. After the installation is complete, go back to the main recovery menu and select reboot system now to reboot the phone and boot up into the Android 4.2 ROM.
  13. Due to changes in the SD card partition location in Android 4.2, some apps data might not restore properly, but other data like Contacts, SMS, bookmarks, etc will restore fine.

NOTE: If you want to go back to your previous ROM, boot into recovery (see step 7), select backup and restore then restore your previous ROM by selecting it from the list.

The Android 4.2 ROM is now installed on your Sprint Galaxy Nexus. Do try it out and let us know how it works, and don’t forget to visit the source page linked above for updates on the ROM and more details.