For Android Galaxy S2 users looking for 4.1.2 Jellybean stable firmware, an XXLSJ based 4.1 firmware version will soon be available for installation on the Samsung Galaxy S2 GT-I9100 model.
The following is the guide for step by step instruction how to install and the prerequisites before doing so.
Pre Requisites before Flashing
ü All the data in the device must be backed up to avoid any possible corruption or data loss.
o SMS - better uses SMS backup and restore app
o Contacts - best to sync them to Gmail application
o Call Log - call log and restore
o Multimedia and other data - copy to external SD card
o APN and MMS Settings - note down from the path "Applications > Settings > Wireless and Network > Mobile Networks > Access Point Names"
ü Enable USB debugging, "Settings > Applications > Development > USB debugging. Make sure that the battery level is at least 40 per cent or the device might turn off during the rooting process.
ü Make sure that the device is not Network Locked. The update may cause bricking on the device is its Network Locked.
This is a custom ROM with 4.1.2 Jellybean Firmware; it only applies to rooted Samsung Galaxy S2 GT I9100. If the device is not rooted yet, here is the procedure:
1. Download Odin (http://cdn.androidadvices.com/wp-content/uploads/2012/07/Odin3-v1.83.exe) and XXLSJ (http://www.gokhanmoral.com/public/files/siyahkernel/v4/Siyah-s2-v4.1.5.tar) to your computer.
2. Extract the firmware package once downloaded.
3. Turn off the Galaxy S2.
4. Proceed to download mode (volume up rocker key + power button at the same time). Retry again if the device proceeds to normal mode.
5. Connect Galaxy S2 to the computer.
6. Open Odin and the ID: COM section will turn yellow indicating that all drivers are installed successfully.
7. Now click the PDA to select the tar file which has been extracted. Start after selection to begin rooting.
8. The phone will reboot after the rooting. The device will not take longer time to reboot.
After the interruption of rooting, proceed with the flashing of 4.1.2 custom ROM Jellybean firmware.
1. Download the Biftor Jellybean ROM Firmware (http://forum.xda-developers.com/showthread.php?t=2026911) to the computer.
2. Connect the device and copy the downloaded zip file to Galaxy S2.
3. Download the ROM Manager app from the Google Play store and select "Reboot into Recovery mode" option from it. The manual recovery mode is the same with rooting process.
4. In the recovery mode, select "Wipe data/factory reset" & Wipe Cache partition".
5. Select the "install zip from SD card" to choose the zip file. Around 3-5 minutes to complete the update.
6. Once update is finished, go back and "reboot the system now".
7. Check the Settings > About Phone to see the firmware version.
Biftor ROM Main Features
ü 13 toggle status bar
ü Transparent status bar
ü 4-way reboot
ü 4 lock screen icons
ü All rotation
ü Long press "back" key to kill app
ü Navigation bar functional
ü Full camera quality
ü DSP manager and Google music player
ü Touchwiz 5 with all rotations and scrolling wallpaper
ü Pop-up browser functional
ü Multi-window functional + toggle for enable/disable in status bar
ü Smart rotate
ü Smart Stay functional
ü Call recording
ü Unlimited SMS recipient list
ü Lags fixed
ü Faster GPS lock
ü Enabled sensor for GPS locking
ü Google Apps functional
Samsung scheduled the official release of the Jellybean updated in January 2013, although it was originally scheduled mid-November.