The latest Android 4.1.1 Jelly Bean JRO03L build was just recently released by Google and now we have a custom ROM based on it for the Samsung Galaxy Nexus GT-I9250.

XDA developer udK made a custom ROM based on the latest Android 4.1.1 build and incorporated a custom Linaro-optimized kernel, providing faster and smoother performance. The ROM, based on the latest build, is made even better because of the added kernel and some tweaks here and there. If you have a Samsung Galaxy Nexus in your hands, maybe it's time you dress it up in Jelly Bean through this custom ROM.

Just like other custom ROMs, this one may also carry some issues and bugs but don't let these stop you from testing the ROM out.

In this guide, learn how to upgrade the Galaxy Nexus I9250 to Jelly Bean build JRO03L with Linaro kernel.

Warning

• The instructions in this guide are intended for use with the Samsung Galaxy Nexus, model number GT-I9250. Applying these instructions on another device or model may produce undesired outcomes.
• The information in this guide is provided for instructional and educational purposes only. There is no guarantee that these instructions will work under your specific and unique circumstances.
• Use these instructions at your own risk. We shall not hold any responsibility or liability for whatever happens to you or your device arising from your use of the info in this guide.
• Read and understand the whole guide first before actually performing the instructions.

Requirements

• A Samsung Galaxy Nexus GT-I9250 with an unlocked bootloader and ClockworkMod Recovery installed. For help, check these guides:
  • How to unlock the Galaxy Nexus’ bootloader
  • How to root and flash ClockworkMod Recovery on the Galaxy Nexus
• Your phone's USB cable
• A RAR extraction tool such as WinRAR or 7-Zip
• Download the AOSP Jelly Bean 4.1.1 JRO03L ROM package (AOSP_JRO03L_07-08-2012.rar, md5sum: 175f0b4abfd1fe82653a5e48a956dd57) to your computer.
• See to it that your phone's battery is charged to 75% or more to avoid interruptions during the process.
• Backup all personal data on your phone to make sure you have a copy of your personal data (e.g., contacts, SMS, MMS, Internet settings, Wi-Fi passwords, and the like) in case the procedure in this guide erases such data.
  • For backup tips, check our guides on how to sync your data to the cloud and how to create local backups of your mobile data.

Instructions

1. Extract the RAR file.  You will get a ZIP file called update_signed_07.08.2012.zip.  Copy this extracted ZIP package to your phone's SD card.
2. Switch your phone off and boot into ClockworkMod Recovery. To do this, press and hold down the Volume Up, Volume Down, and Power buttons together until recovery boots.
3. Highlight Restart Recovery using the Volume keys and select it using the Power button.
4. Make a NANDroid backup of your existing ROM in case of problems with this ROM. To create a backup, go to Backup and Restore and select Backup.
5. Select Wipe data/factory reset and confirm the action on the next screen. Wait for the process to finish.
6. Select Install ZIP from SD card.
7. Select Choose ZIP from SD card and browse to ROMfile and select it. Confirm the action on the next screen to start installing the ROM to your phone.
8. After installation is complete, go back to the main menu and select Reboot system now. This will reboot your phone to the newly installed ROM.

Awesome! You have successfully installed the AOSP-based custom Android 4.1.1 JRO03L ROM to your Samsung Galaxy Nexus GT-I9250. With a faster OS, you'll definitely love your Android phone even more.