The Android 4.1 Jelly Bean was launched several days ago and since then numerous versions of its were leaked, ROMs that you can use to update Galaxy Nexus GSM and Verizon variants or even HTC One X. Now, an XDA developer managed to create an unofficial build of Jelly Bean for Galaxy S3 and if you ‘re a owner of such device, then you should follow the instructions in this post and learn how to successfully get Android’s latest firmware ROM and see what new features is packing.
This guide is for Android advanced users and you shouldn’t try to apply it on your Galaxy S3 if you don’t know your way around CWM Recovery, rooting tools and other similar software. Remember that this guide contains an unofficial port of Jelly Bean from Galaxy Nexus OTA update leaked files.
Installing the Android 4.1 Jelly Bean on your Galaxy S3 should be done only if you’ve created a full backup of the currently installed ROM. That’s because this Unofficial Jelly Bean release is unstable and you might regret installing it after a few days. The official Android 4.1 Jelly Bean ROM for Galaxy S3 I9300 wasn’t announced but we should expect that in the near future more and more XDA developers will manage to get their hands on it and then we will create a tutorial that teaches you how to upgrade from ICS to Jelly Bean Android OS.
Jelly Bean unofficial ROM features a faster and smoother interface, offline voice typing, improved Google Search service, improved notifications area and multiple other small features that you’ll be able to test only if you flash the files I’ve listed in the tutorial guide. Before we can start to update your device, you should read the pre-requisites info and learn how to correctly prepare your Galaxy S3 I9300 for the ROM upgrade process. Here’s what you need to know and learn how to backup the currently install ROM apps, APN Settings, SMS and all other files:
- install this Unofficial Android 4.1 Jelly Bean only on the Samsung Galaxy S3 I9300 model number. Do not flash the ROM on a different smartphone as you might end up damaging it.
- install this ROM only on SGS3 devices that have been rooted and have CWM Recovery installed on them.
- charge the phone’s battery until it reaches at least 70% in power levels. This won’t let the phone switch off while you’re installing the new ROM.
- in the tutorial steps you will be asked to wipe all phone data, action which forces you to create backups of the files currently stored on your device. Move them on your computer or place them on the internal / external sdcard.
- backup your APN Settings, SMS, Call Logs and the installed applications using these Android utilities: AppBAK for Android apps backups | SMS backup & restore | Call Logs backup & restore | APN Settings Backup & Restore.
- to save all your phone contacts, you will need to sync them with your Gmail account. This guide HERE teaches you how to do it correctly.
- because this unofficial ROM is highly unstable you should create a full backup of the ROM firmware that you’re running right now on your phone. It can be done from CWM Recovery, ROM manager etc.
- install the Samsung USB drivers and make sure that you enable USB debugging mode.
- we cannot be held responsible if you brick the Galaxy S3 with this ROM and you should only use this guide if you’re an advanced Android user.
This leaked Android 4.1 Jelly Bean ROM for Samsung GS3 has some features that aren’t working and you should know this before moving the tutorial guide. Wi-Fi, Bluetooth, NFC, Audio, Camera and other functions aren’t working and as I said that’s because it isn’t an official release for S3 but a ported ROM from Galaxy Nexus ROM. However, the ADB, touchscreen, notification LED, hardware acceleration, Cellular Radio, SMS, Physical buttons, accelerometer, charging are working smoothly.
Make sure that you backup your currently installed ROM and only afterwards you should move to the tutorial guide . Use the comments section to tell us what other Jelly Bean features aren’t working in this release. Also, use the comments section to ask for help in case you cannot apply this unofficial Jelly Bean ROM firmware.
How to install Android 4.1 Jelly Bean unofficial ROM on Galaxy S3 I9300:
- Download the leaked ROM zip file by clicking HERE. Save the file on your PC and do not unzip its contents.
- Next, connect your S3 to your computer and then move the ROM zip package on its internal SD card. After you move the file, you need to power OFF the phone and then you will need to boot into recovery mode.
- Enter CWM Recovery mode by holding simultaneously these Galaxy S3 buttons: volume up + home + power. Release the buttons when custom recovery main menu appears.
- Now create a full backup of your currently installed ROM. Select ‘Backup and restore’ and after that select ‘backup’ and wait until CWM recovery completes this process. Please note that your device’s internal sdcard should have at least 1GB of free space before starting the backup process.
- Return to the main CWM recovery screen and select ‘wipe data/ factory reset’. Confirm that you want to delete all files. Note that this process won’t delete the contents of your phone’s internal or external sdcard.
- When the data has been wiped you need to select ‘install zip from sdcard’ and from the next recovery screen select ‘choose zip from sdcard’.
- Locate the ROM zip file moved on your phone at step 2 and select it for installation.
- Confirm the you want to flash this new ROM and then wait until the process is complete.
- When all files have been installed you will need to return to the main recovery screen and select ‘reboot system now’.
- The Galaxy S3 I9300 device will now boot into Android 4.1 Jelly Bean ROM firmware and you should allow it to complete this first boot.
- When the Jelly Bean homescreen appears, you are free to enter your Google credentials and now you can begin the test of Google’s latest Android release. That’s it, your device has been successfully updated.
Please note that in case the device gets stuck or it goes into a boot loop then it was surely bricked and you should try to enter recovery once again and repeat the tutorial guide. The second time you should be able to install it successfully if you don’t skip any of the steps listed in the tutorial guide. An alternative method would be to restore the phone to a stock firmware and after that you will need to re-root it and install CWM Recovery.
The above note shouldn’t scare you as the Galaxy S3 isn’t a device that gets bricked easily. In case you do have problems then you should leave a comment under this article and describe exactly what actions you took prior and during the tutorial process, as it is most likely that you forgot to apply one of the steps listed above.
If you have any tips and tricks regarding Galaxy S3, Jelly Bean 4.1 or Ice Cream Sandwich ROMs then you should tell us in comments. I hope that you found this guide helpful and that you’ve managed to successfully flash Google’s latest Android 4.1 Jelly Bean firmware even if it is only a Galaxy Nexus port and it might be unstable.
In case you don’t like Jelly Bean or you find that it packs too many features that aren’t working, then you should use the S3 ROM backup file you created at step 4 and restore it. I feel like this is the last instruction I had for you, go test your Galaxy S3 and the leaked Jelly Bean ROM and tell us how it works.