Install official AOKP JB-MR1 Build 3 for AT&T Samsung Galaxy S3 (Android 4.2.1 ROM)

official AOKP JB-MR1 Build 3 for Sprint Samsung Galaxy Nexus

Best Black Friday Deals at: AT&T, Sprint and Verizon.

AT&T Galaxy S3 device can be updated to Android 4.2.1 with the AOKP Jelly Bean MR1 build 3 ROM. This is a monthly release of AOKP JB and you will get tons of new features that will also improve the overall stability and performance of your device.

AOKP JB MR1 build will bring three new UI mode selectors: Phablet, Tablet and Phone. Also you will get the LastApp toggle, transparency for all UI sections, Car Home, Quick Unlock and multiple others. In order to make sure that you successfully install this ROM on your device, you will first need to read the guidelines listed before the ‘how-to’ guide.

Here’s what you need to know in order to make sure that you can install AOKP JB MR1 Build 3 ROM on your AT&T Samsung Galaxy S3 device. These guidelines should help you flash the custom ROM at your first attempt:

  • Don’t use this tutorial on any other smartphone. Use it only for the AT&T Samsung Galaxy S3s device, as it won’t work for any other Android device.
  • The AT&T Samsung Galaxy S3 device should be on an unlocked bootloader, rooted and running a CWM Recovery image. Without these you won’t be able to flash any customization files on your device.
  • Before you can get to the tutorial you will have to create a NANDROID backup of your current ROM. This will act as a restore point for your device in case the guide doesn’t complete successfully and your phone is unable to boot with the new ROM.
  • The tutorial will tell you to wipe data and factory reset your smartphone in order to flash the new OS, but you will delete only the system partition and the Internal SD card will remain intact. Now, since you will reset the system partition, you will lose the apps, call logs, SMS and other similar data which is why you should use the following tools in order to backup such data:  SMS backup & restore | Call Logs backup & restore | APN Settings Backup & Restore | AppBack for Android application. Root access is needed by some of these tools.
  • Sync your People / Contacts app with your Gmail account. Remember to enter the same Google Account after installing the new ROM.
  • Enable the USB debugging option.
  • Charge the phone’s battery until its power level goes over 5o%. This will prevent the device from powering off during the update.
  • Use this guide only if you’re an advanced Android user and don’t skip any steps listed below.
  • Note that we cannot be blamed in case something goes wrong and you brick the phone nor in case you lose any data files. Make sure to read the entire tutorial.
  • If you’re having problems completing the install then you should ask for more help in our comments section.

These were all the instructions that you had to go over. Now you can get to the tutorial and learn how to successfully flash the new AOKP build OS.

How to update AT&T Samsung Galaxy S3 with AOKP JB MR1 build ROM:

  1. Download the ROM from HERE. Save the file on your PC and don’t unzip.
  2. Download the Gapps for Android 4.2.1 from HERE. This is the tool that you will have to flash in order to get all Google-based applications. Do not unzip this file and save it on your PC.
  3. Connect your device to your PC.
  4. Move the AOKP JB MR1 build 3 ROM and Gapps files on your device’s internal SDcard. Disconnect the device when the files are copied. Power off the device.
  5. Now, boot your device into Custom Recovery mode. It can be done if you press at the same time Volume Up, Home and Power. Release the buttons when the custom Recovery menu appears.
  6. Select ‘wipe data/ factory reset’ option. Confirm this process. NOTE: If you’re already running an Official AOKP JB rom then you can skip this step.
  7. Select ‘install zip from sdcard’ and then ‘choose zip from sdcard’. Find the ‘AOKP JB MR1 build 3 ROM and confirm its installation.
  8. Select again ‘choose zip from sdcard’ and then flash the Gapps zip. Confirm.
  9. Get back to the main menu of the Recovery mode.
  10. Select ‘reboot system now’.
  11. The first boot process of this new ROM will now start. It shouldn’t take more than 5 minutes to complete.
  12. Enter your Google Account and take control over your device once again. Test the new ROM and tell us in comments which are its best new features.

These were all the steps that you had to take. Now you can use the AOKP JB MR1 build 3 ROM on your AT&T Galaxy S3.

In case the update isn’t installed at your first attempt then you should retry until you manage to complete it. The second time you should make sure that you apply the step 6 as that might be the reason why your phone cannot be updated. For more tips use the comments section.