Update Nexus S to Jelly Bean Android 4.1 [Guide]

The first fully working Android 4.1 Jelly Bean ROM for the Nexus S has been released, built from the official Jelly Bean sources by XDA Forum Member htchoi5609, so that instead of waiting for the official update by Google (which should start rolling out any day now) people can simply flash this ROM to get a taste of Jelly Bean and all its features, specially smoother and faster performance and interface.

Let’s take a look at how the Jelly Bean Android 4.1 ROM can be installed on the Nexus S.


This ROM and the guide below are compatible only and only with the international GSM Nexus S. It’s not compatible with any other device. Check your device model in Settings » About phone.


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 AOSP Jelly Bean Android 4.1 ROM on Nexus S

  1. This procedure will wipe all your apps, data and settings. Backup your Apps and important data — bookmarks, contacts, SMS, APNs (internet settings), etc. This Android backup guide would help you.
    Important! Don’t forget to at least make a backup of your APN settings, which you can restore later if your data connection does not work after installing the ROM. Use the backup guide to find out how.
  2. Make sure the bootloader on your Nexus S is unlocked and you have ClockworkMod recovery installed. You can use the Nexus S toolkit here to install ClockworkMod recovery.
  3. Download the latest version of the ROM from the official development page.
  4. Download the Google Apps package. This will install apps like Market, Gmail, etc. which are not present in the ROM.
    Download Gapps  |  Alternate Link  |  Filename: gapps-jb.1.zip
  5. Copy the downloaded zip files from step 3, 4 and 5 to the SD card. Do not extract them.
  6. Boot into ClockworkMod recovery. To do so, turn off the phone. Then, press and hold the Volume Down and the Power buttons together to boot into fastboot mode. Here, highlight the RECOVERYoption by navigating to it using the volume buttons, then select it using the Power button to boot into recovery.
    In recovery, use the volume buttons to scroll up/down and the power button to select an option.
  7. 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. 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.
  8. Select wipe data/factory reset, then select Yes on next screen to confirm. Wait a while till the data wipe is complete.
  9. Select install zip from sdcard, then select choose zip from sdcard. Scroll to the ROM file on the SD card and select it. Confirm installation by selecting Yes – Install _____.zip on the next screen. The ROM will start installing.
  10. After ROM installation completes, select choose zip from sdcard again, then select the gapps-jb.1.zipfile to install the Google apps package.
  11. After Gapps installation is complete, select go back then select reboot system now to reboot the phone into Jelly Bean.
  12. Returning to Previous ROM: To go back to your previous ROM, boot into recovery, select backup and restore then restore your previous ROM by selecting it from the list.

Android 4.1 Jelly Bean is now installed and running on your Nexus S. Visit the official development page for more info and to get the latest updates on the ROM. Share your thoughts on the ROM in the comments.