Samsung announces Android 4.3 Jelly Bean but Google released Android 4.3.1 version prior to Android 4.4 KitKat. If you want the so-called 'pre-KitKat OS,' you can download and manual flash the Android 4.3.1 right to your Samsung Galaxy S3.

SlimBean ROM Update with Android 4.3 Jelly Bean

Aside from the features of Slim ROM running Android 4.3 such as Bluetooth Smart, OpenGL ES 3.0 and virtual surround sound, here are some changes on the Android 4.3.1 Jelly Bean version:

- Fixes problems with All-in-One Google Apps on Exynos 4 chipset

- Updated YouTube app

- Updated Google Play Store

- Added Latin IME for better compatibility with other ROMs

- Several minor bug fixes

Warning: This Android 4.3.1 Jelly Bean firmware is not an official ROM from Samsung. Manually flashing custom ROM may damage your Galaxy S3. We are not responsible for any errors or damages which occur on your device. Read, follow and understand the procedures carefully. Do this at your own risk!

Requirements:

1. This firmware is designed for the Samsung Galaxy S3 GT-I9300 model only. Do not flash this to any other variant.

2. Root the smartphone and Install a ClockworkMod recovery on your Samsung Galaxy S3 GT-I9300.

3. Install the necessary USB drivers for your Galaxy S3 on your computer.

4. Create a backup of all personal information, settings and data files stored on your handset.

5. Make sure that the battery level is at least 50 per cent to avoid power interruption.

6. Enable USB debugging mode on your device. Go to "Settings > Applications > Development > USB debugging mode" or "Settings > Developer options > USB debugging."

7. Download the SlimBean Android 4.3 ROM for the Galaxy S3 GT-I9300 and the Slim All-in-One Google Apps or Minimal Google Apps package to your computer.

Flashing Instructions:

1. Connect your Samsung Galaxy S3 GT-I9300 to the computer using a USB cable.

2. Copy the SlimBean Android 4.3 Build 2 ROM and the chosen Google Apps package to the SD card of your smartphone. No need to extract any of them.

3. Disconnect the smartphone from the computer then switch it off.

4. Reboot into Recovery mode by pressing and holding the Volume Up, Home and Power keys at the same time till the Samsung logo appears.

5. Inside the Recovery mode, create a nAndroid backup of the current ROM. Select "backup and restores > backup." The ROM will be saved inside the SD card of your Galaxy S3.

6. Perform a full wipe on your device. Select "wipe data/factory reset" and "wipe cache partition." Then select "advanced > wipe Dalvik cache."

7. Go back to the main menu then install the SlimBean Android 4.3 Build 2 ROM. Select "install zip from SD card > choose zip from SD > search the ROM you have copied earlier > confirm installation." Apply the same with the Google Apps.

8. Once the installation has been completed, go back then select "reboot system now."

9. Your Samsung Galaxy S3 smartphone will reboot and may take up to five minutes before reaching the home screen.

Congratulations! The Samsung Galaxy S3 GT-I9300 is now running Android 4.3.1 Jelly Bean with added features and minor bug fixes from Slim ROM.

In case you have any issues or problems, send your feedback to Bugs Section of Slim Bean Web site.