Team Kang has surely been busier than bees in the past weeks. It just released the first build of its Jelly Bean ROM to a number of devices and one of those blessed devices is the T-Mobile Samsung Galaxy S3 SGH-T999.

The phone was slated to receive an official Jelly Bean update very soon, but developers are just really too kind, providing users alternatives instead of waiting for a few more weeks.  It is understandable for users to get quite antsy because it is Jelly Bean we are talking about, the fastest and smoothest Android OS to date.

Now that the official AOKP Jelly Bean ROM has been released, you can all bid bye bye to all the bugs and issues you have encountered from the unofficial and preview releases of ROMs.

This guide shows you how to upgrade the Galaxy S3 T999 to Android 4.1.1 Jelly Bean via AOKP Jelly Bean ROM (official).

Warning

• The instructions in this guide are intended for use with the T-Mobile Samsung Galaxy S3, model number SGH-T999. Applying these instructions on another device or model may produce undesired outcomes.
• The information in this guide is provided for instructional and educational purposes only. There is no guarantee that these instructions will work under your specific and unique circumstances.
• Use these instructions at your own risk. We shall not hold any responsibility or liability for whatever happens to you or your device arising from your use of the info in this guide.
• Read and understand the whole guide first before actually performing the instructions.

Requirements

• A T-Mobile Galaxy S3 SGH-T999 with ClockworkMod Recovery installed
  • For help, check our guide on how to install ClockworkMod Recovery on the T-Mobile Galaxy S3.
• Your phone's USB cable.
• Download the following to your computer:
  • Any of the following Official Jelly Bean AOKP Build 1 ROM packages (aokp_d2tmo_jb-build-1.zip, md5sum: 0372fee23abe9adedd2cc14a978cafa6)
    • Download Link 1
    • Download Link 2
  • GApps (Google Apps) package (gapps-jb-20120726-signed.zip, md5sum: f62cfe4a827202899919fd932d5246d7)
• See to it that your phone's battery is charged up to 75% or more to avoid interruptions during the process.
• Backup all personal data on your phone to make sure you have a copy of your personal data (e.g., contacts, SMS, MMS, Internet settings, Wi-Fi passwords, and the like) in case the procedure in this guide erases such data.
  • For backup tips, check our guides on how to sync your data to the cloud and how to create local backups of your mobile data.

Instructions

1. Copy the AOKP ROM package and the GApps package to your phone's internal SD card.
2. Switch your phone off and boot into ClockworkMod Recovery. To do this, press and hold down the Volume Up, Home, and Power buttons together until the screen turns on.
   • NOTE: You can use the Volume keys to navigate and the Power button to select an item or option in Recovery Mode.
3. Make a NANDroid backup of your current ROM in case of problems. To create a backup, go to Backup and Restore and select Backup.
4. Select Wipe data/factory reset and confirm the action on the next screen. Wait for the process to finish.
5. Select Install ZIP from SD card.
6. Select Choose ZIP from SD card and locate the AOKP ROM file. Select the file and confirm the action on the next screen to start installing the ROM to your phone.
7. Once installation of the ROM is done, install the GApps package in the same manner as in steps 5 and 6. Wait for the installation to finish.
8. Select Go back and choose Reboot system now. This will reboot your phone to the newly installed AOKP Jelly Bean ROM.

Great job! You have successfully installed the official AOKP Jelly Bean ROM on your T-Mobile Samsung Galaxy S3 SGH-T999. How are you liking the ROM so far? Share your thoughts by leaving a comment below.