Users of AT&T Samsung Galaxy S3 can finally install Android 5.0 Lollipop update, though with the use of a custom ROM only.

The final official update made available for the Samsung Galaxy S3 is the Android 4.1.1 Jelly Bean, according to GSM Arena. Officially, Google's latest Lollipop update will not be released for the 2012 smartphone but thanks to genius custom Android developers, AT&T Samsung Galaxy S3 owners can opt to upgrade their smartphone's OS with the use of a custom firmware.

Accordingly, CyanogenMod or CM12 series Alpha version based on Android 5.0 Lollipop is available for the Galaxy S3 units bearing the model number SGH-I747. The custom firmware was developed by XDA Developer forum member known as 'pandasa123.'

Since the CM12 Alpha ROM is still in experimental stage, bugs and firmware issues are still to be expected. Also, S3 users who will install the CM12 firmware need to make sure that there is enough memory space on the smartphone. Reportedly, the custom ROM weighs 226 MB.

Also, it is important to be very punctilious during the installation process to avoid mistakes that might cause potential damage to the device. Follow the detailed guide posted on this IB Times report to install the Lollipop custom ROM successfully on Samsung Galaxy S3 SGH-I747.

Meanwhile, below are some of the requirements to meet even before proceeding to install the firmware:

Check the battery level. The smartphone needs to have at least 80% battery to avoid power interruption issues when installing the firmware.

Create a backup of all the important data and settings stored on the Galaxy S3. It is recommended to use ClockWorkMod or TWRP as custom recovery tools.

The proper USB drivers for the Galaxy S3 should already be installed on the PC so the Android device will easily connect to the computer when installation is about to begin.

Turn on the USB Debugging Mode on the smartphone.