While custom ROMs allow developers to re-imagine software and present them to users the way they want it, some people just want to stick to the classics. No frills, no extra features, just software the way it was supposed to be.

Galaxy Nexus users can certainly enjoy a pure Jelly Bean experience with this ROM. Built by XDA Developers member AndroidUser00110001, the pure vanilla AOSP Jelly Bean ROM was built from AOSP and Android 4.1.1 build JRO03H. This ROM is for the user who wants the pure Android experience. Nothing, except root and Busybox, have been added to the ROM.

The ROM is still in its first release, so it shouldn't be surprising to see a few bugs and issues. The developer hasn't mentioned any major bugs so make sure to keep your eyes out for them if you encounter them.

In this guide, learn how to upgrade the Galaxy Nexus I9250 to Jelly Bean build JRO03H.

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

• Galaxy Nexus with an unlocked bootloader and ClockworkMod Recovery installed.
  • See our guide on how to unlock the bootloader on your Galaxy Nexus GT-19250.
  • See our guide on how to install ClockworkMod Recovery on your Galaxy Nexus GT-I9250.
• Download the following:
  • pure vanilla AOSP Jelly Bean ROM file (AU_maguro_411_V1.zip, md5sum: f98e454807b3dac6b17cf7eb42febde2)
  • Google Apps package (gapps-jb4.1.1-08032012.zip, md5sum: 8b6f6968ee27442f52299264ecd3015c)
• 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. Copy both the pure vanilla AOSP Jelly Bean ROM file and the Google Apps package to your device's SD card.
2. Turn off the phone.
3. Boot into Recovery by pressing and holding down the Volume Up, Volume Down, and Power buttons until the screen turns on. Scroll to Restart Recovery with the Volume buttons and select it using the Power button.
4. Make a NANDroid backup of your current ROM. Select Backup and Restore and select Backup.
5. Select Wipe cache partition. Confirm the action on the next screen.
6. Select Wipe data/factory reset. Confirm the action on the next screen.
7. Select Advanced and then select Wipe Dalvik cache. Confirm the action on the next screen.
8. Select Install ZIP from SD card.
9. Select Choose ZIP from SD card and choose the Pure Vanilla AOSP Jelly Bean ROM file.
10. Once the Jelly Bean ROM has finished installing, flash the Google Apps package in the same way as in steps 8 and 9.
11. Select Go back.
12. Select Reboot system now.

Congratulations! You can now enjoy the AOSP-based Android 4.1.1 Jelly Bean build JRO03H on your Samsung Galaxy Nexus GT-I9250.