Tips & Tutorials

Update T-Mobile Galaxy S3 SGH-T999 to Android 4.2.1 AOKP Build 2 Jelly Bean custom ROM

T-Mobile Galaxy S3 SGH-T999 Android 4.2.1 AOKP Build 2 Jelly Bean custom ROM is now available for download. It was released yesterday for all the Galaxy S3 variants. There is no word from Samsung on when they would release the official Android 4.2.1 software update for the Galaxy S3, but all thanks to the Android Open Kang Project (AOKP), we can already enjoy Android 4.2.1 Jelly Bean with the custom firmware. You can update T-Mobile Galaxy S3 SGH-T999 to Android 4.2.1 AOKP Build 2 Jelly Bean custom firmware using the tutorial below. ClockworkMod recovery is not required at all.

As you continue reading below, we will guide you through the entire process of how to install Android 4.2.1 AOKP Build 2 Jelly Bean on T-Mobile Galaxy S3 SGH-T999 with complete steps. Please make sure you backup all your data as given below because this tutorial will wipe your data. Also, don’t forget to read the given additional tips that you have to keep in mind before proceeding to the tutorial on the next page. Let’s get to the tutorial now.

T-Mobile Galaxy S III SGH-T999 - Android 4.2.1 AOKP Build 2 Jelly Bean

Disclaimer: All the custom ROMs and firmwares, official software updates, tools, mods or anything mentioned in the tutorial belong to their respective owners/developers. We ( or the developers are not to be held responsible if you damage or brick your device. We don’t have you on gun point to try out this tutorial 😉

Android 4.2.1 AOKP Build 2 Jelly Bean Firmware Details:

The latest build of AOKP Android 4.2.1 ROM is again about new features, minor changes throughout the ROM and fixing bugs for your T-Mobile Galaxy S3. Here is the list of features added/changed in this ROM:

  • New features
    • General UI
      • Boot animation picker enhancements
      • Colorable clock views/widgets
    • Lockscreen
      • Option to hide initial page hints
      • Start lockscreen with minimized challenge
      • Longpress on minimized challenge to unlock
      • Carousel animation
    • Navigation Bar
      • Colorable NavBar background
      • Recents menu opens with lightning speed
    • Statusbar
      • Alternative signal layout (GB-style)
      • New toggle: Sound state (ring/vib/silent)
      • Mobile technology indicator reflects internet connection status
    • Camera
      • Powerkey shutter
    • Phone
      • Call statistics – Phone app / local menu

Known issues

  • Hiding page hints on the lockscreen isn’t working if the carousel animation is active.
  • Recents RAM Bar is not updating correctly.
  • Only on Galaxy S3 variants: A2DP/in-call volume adjustment, WiFi tethering are not working and you might find the speakerphone volume level a bit too low.

UPDATE: AOKP Build 3 custom ROM is now available for this phone. Read there tutorial here!

T-Mobile Galaxy S3 USB Drivers

You will need to connect your Android phone with the computer. For that, please make sure you have installed the USB drivers for T-Mobile Galaxy S3 properly. If not, you can download the latest official drivers from our Android USB Drivers section here:

Download T-Mobile Galaxy S3 USB drivers!

Backup and Other Important Tips

Done with the USB drivers? Perfect. The tutorial is on the next page, but first, please take a look at the following tips and important points you need to take care of. These are important, as we don’t want anyone losing their personal data or apps:

Always backup your important data that you might need after you install a new custom ROM, an official software update or anything else. Make a backup for just in case, you never know when anything might go wrong. See below for some tips on how to backup data:

Samsung users can also back up data using Samsung KIES. If you backup data manually, you get more options what to choose from and it is very easy to move data across Android devices from different manufacturers, i.e moving Samsung Galaxy Note backup data to HTC One X.

If you already have a custom recovery (ClockworkMod, TWRP etc.) installed on your phone, we strongly recommend a backup using that as it creates a complete image of your existing phone set up.

A few more optional tips that you should remember:

1. Having problems connecting your Android phone to the computer? You need to enable USB debugging mode. See here: How to Enable USB Debugging — for Gingerbread, Ice Cream Sandwich and Jelly Bean.

2. Make sure your Android device is charged up to 80-85% battery level. This might help you: How to Check Battery Percentage. Why? Because, if your phone goes off suddenly while installing a custom ROM, flashing an official firmware update or installing mods etc. — your phone might get bricked or go dead permanently. No one wants that, right?

4. Most of the tutorials and how-to guides on Team Android are for factory unlocked Android phones and tablets. We recommend NOT to try our guides if your phone is locked to a carrier, unless we have specified the carrier name or device model.

If you find the above tips useful and they were helpful to you, please consider giving us a +1 or LIKE to thank us!

All set and ready? Good. You can now proceed with the tutorial on the next page and update T-Mobile Galaxy S3 SGH-T999 to Android 4.2.1 AOKP Build 2 Jelly Bean custom firmware.

About the author

Taimur Akmal

Devoted writer, enjoys developing code. Appreciates excellent food, exceptional coffee and great company. He is also into sublime design and nicely built cars.

1 Comment

  • i did everything how it stated but one it booted back up it showed the nexus x and then it said unfortunately wizard setup has stopped and unfortunately the has stoped… please help

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