A custom firmware with Android 4.4 KitKat update is now available for two variants of Samsung Galaxy S3.

The official Android 4.4 KitKat update has only been released for the Nexus 5, but the latest Google OS is expected to arrive on other Nexus devices and Android devices. And while waiting for the official build, a number of custom ROMS based on Android 4.4 KitKat update were already released.

According to UberGizmo, one of the latest unofficial Android 4.4 KitKat firmware available now is CyanogenMod11. Those who are interested to install Android 4.4 KitKat update on Samsung Galaxy S3 can already do so, thanks to CM11 firmware.

The Android 4.4 KitKat unofficial firmware is particularly compatible to Samsung Galaxy S3 with model numbers I747 and T999, the variants for AT&T and T-Mobile, respectively.

To thosw who wish to install Android 4.4 KitKat update on Samsung Galaxy S3, you can access the firmware for AT&T model here. Meanwhile, check out the download link of Android 4.4 KitKat update firmware for T-Mobile on this post. The instructions on how to install the custom firmware are also included on each posts.

Since CM11 is an unofficial Android 4.4 firmware, Samsung Galaxy S3 users should take note that flashing the ROM may cause serious damage to the device. Thus, it is important to follow the installation instructions of the firmware. Moreover, before installing Android 4.4 KitKat update, make sure to create a backup first of all the data and settings stored on your device. One can use custom recovery tools like ClockWorkMod to have backup of the device.

Also, those who will install Android 4.4 KitKat update should also expect to encounter a few bugs as the ROM is still in beta-phase, even though it is a source-built. The battery level of the Samsung Galaxy S3 I747 and T999 should be 80 percent or higher before installing the ROM to make sure that the device will not experience power interruption during the process.