If you are using Samsung Galaxy S3 and would like to update your phone to Android 4.1.2 Jelly Bean then you can do this easily through firmware using build number GT-I9300. Android 4.1.2 Jelly Bean has been already officially released for Samsung Galaxy S3 by Samsung, particularly for the International version with model number GT-I9300. For other versions with different build number having no custom firmware, Android 4.1.2 Jelly Bean can be installed by connecting the phone to a computer and installing official Android 4.1.2 Jelly Bean through the KIES utility.
Over The Air update (OTA) for Samsung Galaxy S3 is also available, all you need to do is – go to phone settings > click on About Phone > and then update through Software Update.
Kindly note that the firmware to update official Android 4.1.2 Jelly Bean to Samsung Galaxy S3 is only available in Netherland. However as firmware XXEMG6 is an unrecognized (unofficial) version of software update, it can be updated to any Samsung Galaxy S3 having model number GT-19300, despite country restrictions.
In any case if you are unable to update your phone (Galaxy S3) using OTA or KIES methods, you can manually update the software through these simple steps.
Connect your Samsung Galaxy S3 to your PC using original USB driver.
Use Android SDK by enabling USB debugging mode.
Make sure your battery level is not less than 80% to install official Android 4.1.2 Jelly Bean.
Please note this process can wipe out all your data’s, so you need to create a backup of all your data’s through custom recovery tool like TWRP or ClockWorkMod.
Last but not the least you must be aware of the fact that XXEMG6 Android 4.1.2 Jelly Bean is only compatible for Galaxy S3 having model number GT-19300. In case you are updating this software for other model numbers, it may damage your device.
To explain the process in detail lets check out the comprehensive process to update Samsung Galaxy S3 via Odin.
How to update Android 4.1 jelly bean on Galaxy s3 via Odin.
1: Start your wi-fi internet or internet browser on your mobile to download Odin 3.37.zip file for the update. Now extract this zip file in a computer folder.
2: Now download I9300XXEEMF6 I9300OLBEMF3 XM.zip and extract this file which will provide .tar or .tar.md5 .
3: Switch off your cell phone and press the Volume Down Key, Home Button and Power Button to enter the download mode.
4: You will see a warning sign during this process and after that you will have to press Volume Up Key to continue the process.
5: Install Odin executable file by double click on Odin3 v3.07exe File. Now connect your cell phone with your computer via USB cable.
6: After the connection you will see an “Added” message in the message box. Then Odin will detect your cell phone. Now click on the PDA button and select .tar or .tar.md5.
7: Flash .tar or .tar.md5 in your cell phone by clicking start button. It will show a pass message for the success flashing of .tar or .tar.md5.
8: Now your cell phone would start reboot automatically.
After the whole process, installation of Android 4.1 jelly bean on your phone is complete.
What changes will this update bring to your cell phone?
The update will provide a new feature Auto Share with NFC which enables users to share videos and pictures with other NFC and S-Beam enabled devices.
It will also bring new changes in camera photography features including paper artist and best face options.
This update includes Multi window which allows users to use different apps at the same time on the cell phone screen.
It will provide smart features including smart Wi-fi, live TV, calendar, drive mode, S-voice and more