The Galaxy S2 I9100 has received a flurry of custom ROM Jelly Bean updates and a handful of official Jelly Bean firmware in recent times. The device is garnering much attention from third-party custom ROM developers, thanks to its popularity with Android fans. The smartphone is also enjoying regular official Jelly Bean updates from Samsung, owing to the rising demand for the latest Android firmware from users. The new Android 4.1.2 ZSLSJ firmware is a follow-up version to the ZSLSE official firmware for China/Taiwan/Hong Kong that was released just a few days back.

Galaxy S2 I9100
Galaxy S2 I9100 Gets Official Android 4.1.2 Jelly Bean Update via ZSLSJ Firmware .

Although the latest firmware is officially available only in China and Taiwan through Samsung KIES, it is now possible to download and install the same on any unlocked Galaxy S2 I9100. Those who missed the opportunity to update the firmware via official channels can follow our step-by-step guide below to install it manually with ODIN flash tool.

Key Features Supported on Android 4.1.2 ZSLSJ Jelly Bean Official Firmware

  • Buttery Smooth Performance & Great Stability (Thanks to Project Butter)
  • Full User Interface Revamp (Same UI as of the Galaxy S III and Galaxy Note II)
  • TouchWiz Nature UX
  • Samsung's S Cloud services
  • New Lockscreen With Many Customization Options
  • New Features like Direct Call, Smart Stay and Pop-up Play
  • New Widgets (From Galaxy S III)
  • Free 50GB Dropbox Storage
  • 2 Home screen modes
  • New Notification bar With More Notification Toggles
  • Google Now

Key Points to Note

  • ZSLSJ official firmware and the instructions given in this guide are limited to the international variant Galaxy S2 I9100 model only and will not work on any other device. Verify the device's model number by navigating to Settings > About Phone.
  • Verify that the correct USB drivers are installed for the phone on computer (download Samsung Galaxy S2 I9100 USB drivers).
  • Back up important data and settings on phone using one of the recommended custom recovery tools such as ClockworkMod (CWM) or TWRP, as it creates a complete image of the existing phone setup.
  • Ensure that USB Debugging mode is enabled on the phone navigating to Settings > Developer Options (if the device is running on Android 4.0 or later) or Settings > Applications > Development (if the phone is running on Android 2.3 or earlier).
  • Make sure that the phone has at least 80 per cent battery charge to prevent unexpected device shutdown (due to battery drain) during firmware installation, as this may inadvertently brick or damage the device.
  • Double check to see that the device is factory unlocked (not locked to a specific carrier) with CWM recovery installed on it.
  • As this is an official release, ensure that the device is not rooted (download Root Checker app). Unroot the device first (if it is already rooted), before proceeding with the firmware installation.
  • The instructions provided in this guide are meant for reference purpose only. IBTimes UK will not be held liable if the device is damaged or bricked during or after the firmware installation. Users must proceed at their own risk.

How to Install Official Android 4.1.2 Jelly Bean Update on Galaxy S2 I9100 via ZSLSJ Firmware

Galaxy S2 I9100 Gets Official Android 4.1.2 Jelly Bean Update via ZSLSJ Firmware [How to Install]
Galaxy S2 I9100 Gets Official Android 4.1.2 Jelly Bean Update via ZSLSJ Firmware

Step 1 - Download Android 4.1.2 ZSLSJ official firmware for Galaxy S2 on the computer and extract the zip file.

Step 2 - Download ODIN v3.07 which is needed to install the official firmware on the phone.

Step 3 - Power off the phone. Then boot it into Download Mode by pressing and holding Volume Down and Home buttons together, and then tap the Power button until the construction Android robot icon with a triangle appears on screen. Hit the Power button again to progress into Download Mode.

Step 4 - Launch ODIN on computer and connect the phone to it while the phone is still in Download Mode.

Step 6 - When the phone connects successfully, one of the ID: COM boxes indicates yellow with the corresponding COM port number. This process may be time-consuming. So, leave it alone.

Step 7 - Choose the files that must be flashed or installed on the phone, which can be found among the extracted files in Step 1.

  • Click the 'PDA' checkbox and choose the file with 'CODE' in its name.
  • Select the 'Phone' checkbox and click the file with 'MODEM' in its name. Ignore this step if there is no such file.
  • Choose the 'CSC' checkbox and click the file with 'CSC' in its name. Ignore this step if such file is missing.
  • Enable the 'PIT' checkbox and choose the .pit file. Ignore this step if such file is absent.

Step 8 - In ODIN, enable Auto Reboot and F. Reset Time options. In case of the Re-Partition option, enable it ONLY if a .pit file is chosen in the previous step.

Step 9 - Hit the Start button in ODIN and the firmware installation process will begin. It should take just a few minutes to complete.

Step 10 - Once the firmware installation is done, the phone will automatically reboot. When the home screen appears, just disconnect the phone from computer.

Samsung Galaxy S2 I9100 is now successfully updated to Android 4.1.2 ZSLSJ Jelly Bean official firmware. Go to Settings > About Phone to verify the firmware version installed.

[Source: Team Android]