Android 4.1 Jelly Bean Update for Samsung Galaxy S2

How to upgrade the Galaxy S2 I9100 to Android 4.1.1 Jelly Bean via AOSP-based ROM

When will I get Android 4.1 Jelly Bean? This is the question that most Android users are dying to get an answer to. Google has announced that the Nexus series and the Motorola Xoom tablets will be the first in line to receive the updates. But, what about those phones already running Android 4.0 Ice Cream Sandwich such as the Samsung Galaxy S2 GT-I9100? With the help of independent developers, you can enjoy Android 4.1 Jelly Bean ROM on your phone–at least unofficially.
Although Samsung didn’t officially announce the upcoming update, rumors are saying that Samsung is already testing the latest Android OS on its Samsung Galaxy S3 GT-I9300 and Samsung Galaxy S2 GT-I9100. An update would be expected to come around August or September. Since both phones are already running Android 4.0 Ice Cream Sandwich, chances are high that Android 4.1 Jelly Bean will arrive on both of them. If you can’t wait for the official updates to come, you might as well go over to Android development sites and look for ways on how to flash the latest updates to your mobile phone.
Senior XDA developer kalgecin presents us his AOSP-based ROM of Android 4.1 Jelly Bean for your Samsung Galaxy S2 GT-I9100. Flashing this ROM will let you use the latest Android OS on your mobile phone.
Take note that this ROM is still in its experimental stage and may contain a lot of bugs. It is advised that you must be familiar with flashing ROMs and have a good knowledge in Android development before following the steps below.
Read on to learn how to upgrade the Galaxy S2 I9100 to Android 4.1.1 Jelly Bean via an AOSP-based ROM.

Warning

• The instructions in this guide are intended for use with the Samsung Galaxy S2, model number GT-I9100. 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

• Samsung Galaxy S2 GT-I9100 with stock Android 4.0.3 Ice Cream Sandwich XXLPQ firmware and ClockworkMod Recovery installed
  • Check out these guides on  how to flash the XXLPQ firmware and how to flash ClockworkMod Recovery to your mobile phone.
• Download the following files:
  • Android 4.1 Jelly Bean ROM (full_galaxys2-ota-eng.kalgecin.zip, 115.59 MB)
    • Google Drive Link
    • MediaFire Link
  • required kernel (Kernel_Dorimanx-SGII-ICS-V5.3–T-03-06-D-25-07.zip, md5sum: 584274046a2986d885ba807b5782291f).
  • GApps (Google Apps) package (gapps-jb-20120726-signed.zip, md5sum: f62cfe4a827202899919fd932d5246d7)
• 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 the following files to your phone’s internal SD card:
   • full_galaxys2-ota-eng.kalgecin.zip
   • Kernel_Dorimanx-SGII-ICS-V5.3–T-03-06-D-25-07.zip
   • gapps-jb-20120726-signed.zip files
2. Turn off your phone.
3. Reboot your phone into ClockworkMod Recovery by pressing and holding the Volume Up key, Home button (middle key), and the Power button until Recovery boots.
   • Once in Recovery Mode, use the Volume keys to navigate and the Power button to select an option.
4. Create a backup of your current ROM by heading to Backup and Restore from the main recovery menu. Select Backup on the next screen and confirm the action to backup your ROM.
5. Go back to the main menu and perform a full wipe:
   • Select Wipe Data/Factory Resetand confirm the action on the next screen.
   • Select Wipe Cache Partitionand confirm the action on the next screen.
   • Go back to the main menu and select Advanced. From there, select Wipe Dalvik Cacheand confirm the action on the next screen.
6. Navigate back to the main recovery menu and select Install ZIP from SD card.
7. Select Choose ZIP from SD card and locate the full_galaxys2-ota-eng.kalgecin.zip.Confirm the action on the next screen to flash the file to your mobile phone.
8. Head back to the main menu and flash the Kernel_Dorimanx-SGII-ICS-V5.3–T-03-06-D-25-07.zipin the same manner as in steps 6 and 7. Afterwards, do the same with gapps-jb-20120726-signed.zip.
9. Go back to the main menu and select Reboot system now to restart your phone.

Congratulations! You now have Android 4.1.1 Jelly Bean running on your Samsung Galaxy S2 GT-I9100. If you are facing a lot of bugs on your phone, you can try restoring your backup ROM by going to Backup and Restorefrom recovery. You may also follow the guide under Requirements on how to flash the stock XXLPQ firmware to your mobile phone.