Official Android 4.3 Jelly Bean for Samsung Galaxy S3 seems problematic, according to UK users. Fortunately, a highly-functional Android 4.4 KitKat custom ROM is now available for Galaxy S3 GT-I9300 international variant.

OmniROM Android 4.4 KitKat Test Build

Google's greatest and newest Android version 4.4 KitKat is now available for owners of the Galaxy S3 GT-I9300 international model. OmniROM developers made a highly functional custom ROM running Android 4.4 KitKat for Galaxy S3, which may be more stable than the official Android 4.3 Jelly Bean update.

Everything is likely working normal, except for the two known issues posted by one of the developers: Messy video playback and a bit broken camera on pictures.

Warning: OmniROM 4.4 is a custom ROM which requires manual installation that may damage your Galaxy S3. We are not responsible for any damages which may occur on your smartphone. Read, understand and follow the instructions properly to avoid bricking the Galaxy S3. Do this at your own risk.

Requirements

1. Use the Samsung Galaxy S3 GT-I9300 international model only. Flashing this with other variants may cause unforeseen consequences.

2. Root the smartphone and install the ClockworkMod Touch 6.0.32 or later on your Galaxy S3.

3. Create a backup of all your personal information, settings and data files stored on the Galaxy S3. Perform a manual backup instead of using the Samsung Kies PC suite.

4. Make sure that battery life is at least 50 percent to avoid power interruption during the flash.

5. Enable USB debugging mode on your smartphone. Go to 'Settings > Applications > Development > USB 'debugging' or 'Settings' > Developer Options > USB 'debugging.'

6. Install all necessary USB drivers on your computer for the Samsung Galaxy S3 GT-I9300.

7. Download the OmniROM 4.4 and PA Gapps to your computer.

Flashing Instructions

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

2. Copy the OmniROM 4.4 and PA Gapps then paste it on the SD card of your Galaxy S3. Do not extract the zip files.

3. Disconnect the smartphone then switch it off.

4. Reboot into recovery mode by pressing and holding 'volume up + home + power' keys at the same time until the Samsung logo appears.

5. You may use touch controls or hard keys to navigate inside the recovery mode.

6. Perform an Android backup of the current ROM used by Galaxy S3. Select 'backup and restore > backup' to save the ROM. You may restore it anytime you wish.

7. Install the firmware and Google apps by selecting 'install zip from SD card > choose zip from SD card > look for the OmniROM 4.4 you have pasted earlier > confirm installation.' Apply the same method with the PA Gapps.

8. After the installation, go back to the main menu then select 'wipe data/factory reset.'

9. Reboot your device by selecting 'reboot system now.' Wait up to five minutes for your Galaxy S3 to reach the home screen.

Congratulations! Your Samsung Galaxy S3 GT-I9300 is now running the latest Android 4.4 KitKat OS with the help of OmniROM 4.4.

In case the device goes on boot loop, reboot into recovery mode then perform the following:

- 'wipe data/factory reset'

- 'wipe cache partition'

- 'advanced > wipe Dalvik cache'

- 'install zip from SD card

- 'reboot system now'

For any questions or comments, send your feedback to the original XDA thread of OmniROM 4.4.