Owners of the Samsung Galaxy S2 i9100 version can get the update to Jelly Bean 4.1.2 which has come out in Hong Kong, Taiwan and China. It goes by the name of Android ZSLSE and the firmware comes without any branding and the Chinese language packs.
You do have to take into consideration that this isn’t custom firmware and so there are no changes to it and it doesn’t come with ClockworkMod.
The Jelly Bean 4.1 updates provides owners of the Samsung Galaxy S2 with Project Butter along with a new interface by way of TouchWiz UX. It also comes with S Cloud, a lock screen that is customisable, Smart Stay and Pop up Play. Those who make the update will also get 50GB of Dropbox storage. The update brings with it Google Now improvements, a couple of home screens and a new look to the notification bar.
Bear in mind that this is for the international version of the handset only, with the model number being i9100.
Before you go ahead and update you should back-up your handset, along with checking to make sure that USB drivers are installed on the computer.
Go into Settings > Developer options and make sure that USB debugging is enabled and you need 80% battery at least before making the update. Your device should not be locked to a carrier.
You will have to root your handset again after making the update. And you undertake the update at your own risk.
Follow the steps below to update your Samsung Galaxy S2 to Jelly Bean 4.1.2.
Step 1 – Download Android 4.1.2 ZSLSE official firmware for Samsung Galaxy S2 on the computer and extract the zip file.
Step 2 – Download ODIN v1.85 which is needed for installing the official Android 4.1.2 XSLSE Jelly Bean update on Galaxy S2 I9100.
Step 3 – Power off the Samsung Galaxy S2 and boot it into Download Mode. To do so, press and hold 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 Samsung Galaxy S2 is still in Download Mode.
Step 5 – When the Samsung Galaxy S2 connects successfully, one of the ID: COM boxes indicates yellow with the corresponding COM port number. This step may be time-consuming.
Step 6 – Choose the files that need to 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 named ‘.tar or ‘.md5′.
Hit the ‘Phone’ checkbox and choose the file named ‘MODEM’. Ignore this step if there is no such file.
Tap the ‘CSC’ checkbox and choose the file named ‘CSC’. Ignore this step if such file is missing.
Click the ‘PIT’ checkbox and choose the .pit file. Ignore this step if such file is absent.
Step 7 – In ODIN, enable Auto Reboot and F. Reset Time options. In case of Re-Partition option, check it ONLY if a .pit file was chosen in the previous step.
Step 8 – Hit Start button in ODIN and the firmware installation process will begin. It would take just a few minutes to complete.
Step 9 – Once the firmware installation is complete, the Samsung Galaxy S2 will reboot. When the home screen appears, Disconnect the phone from computer. You should now have Android 4.1 Jelly Bean on your Samsung Galaxy S2.