The Samsung Galaxy S3 is one of the most popular Android smartphones of all time mainly because of its incredibly sleek design and its ultra-powerful hardware. Despite the tremendous success of the Galaxy S3, many owners of the device are still waiting to upgrade to Android 4.2.1 Jelly Bean.

Thanks to the massive pool of developers constantly contributing to the Android community, the Galaxy S3 can be updated to Android 4.2.1 Jelly Bean using a custom ROM. Although practically an infinite number of custom ROMs, but in this tutorial, we're going to show you how to optimize the Galaxy S3 using Cyanogenmod 10.1, which is based off of Android 4.2.1.

With Android 4.2.1, the Galaxy S3 can be considered one of the absolute best Android smartphones. Android Jelly Bean introduces several new features to the Galaxy S3 including Google Now and updated application interfaces. In addition, Android 4.2.1 includes "Project Butter," an initiative created by Google to emphasize the development of smooth transition animations and a better experience when switching between multiple apps. In addition to the standard Android 4.2.1 Jelly Bean features, CyanogenMod 10.1 adds several customization features to the operating system including the ability to overclock the processor and several other advanced configurations.

Please note: This method of upgrading the HTC One X to Android 4.2.1 Jelly Bean requires flashing your smartphone. The version of Cyanogenmod 10.1 that can be loaded on the Galaxy S3 is a nightly build, and therefore, there may still be some bugs in the program. Small bugs will be fixed in upcoming updates as developers continue to tweak the operating system. This tutorial is meant to be used as a reference and only works with the international variant of the Galaxy S3 (also known as Galaxy S3 19300 model). The iDigital Times can't be held responsible for anything that goes wrong during this process. Please proceed at your own risk.

Here's how to update the Samsung Galaxy S3 to Android 4.2.1 Jelly Bean using the CyanogenMod 10.1 Custom ROM:

Step One: Prepare your phone to be flashed. Backup all important data. Make sure your phone has at least 75 percent charge. We recommend a full battery charge. Download all the Galaxy S3 USB drivers. Ensure that USBB Debugging mode is enabled on the phone by going to Settings > Applications > Development. Install ClockworkMod Recovery on the device. Download CM 10.1 Android 4.2.1 Jelly Bean ROM. Download Google Apps.

Step Two: Connect the Galaxy S3 to your computer. Copy the ROM and Google Apps zip files to the root of the smartphone's SD card. Don't extract any files. Disconnect the phone the computer and power the phone off.

Step Three: Boot the Galaxy S3 into recovery mode by pressing and holding Volume Up, Home and Power buttons together until the screen turns on. Then, use the volume buttons to scroll and use the Power button to select.

Step Four: Assuming that youv'e already backed up your data, perform a sull data wipe. To do so, choose Wipe Data/factory reset, then hit next on the screen to confirm. Give the phone several minutes to clean itself of all data.

Step Five: Install CM 10.1 from ClockworkMod Recovery by choosing "flash zip from SD card." Also install Google Apps.

Step Six: Once the device has been flashed and has been installed with Google Applications, return to the main recovery menu and tap "Reboot System Now" in order to reboot the phone. When the Galaxy S3 turns back in, it should be running the CM 10.1 ROM. The very first booting time can take up to five minutes, so please be patient.

Step Seven: Enjoy!