Update AT&T Samsung Galaxy S3 to Android 4.4 KK with Official CM 11 Nightly ROM

Install CM 11 Nightly ROM for Samsung Galaxy devices

AT&T Galaxy S3 device has received its own version of CM 11 Nightly ROM. Use this guide in order to learn how to successfully update the device without too many problems.

The official CM 11 Nightly ROM is based on Android 4.4 KitKat AOSP, it packs all of its stock features along with tons of other functions created by the CyanogenMod team. More info about this release can be found at the CyanogenMod blog web page here.

In order to make sure that you flash the new CM 11 Nightly ROM on your AT&T Samsung Galaxy S3 you will first need to take a look at the preparation info below:

  • use this post only with the AT&T model of the Galaxy S3.
    - do not attempt to update any other Android tablets or smartphones with the files that you find in this article.
  • your device has to be rooted and running the latest CWM Recovery image.
    - you can TWRP too, but we didn’t test it, so you can’t say for sure that it works.
  • ‘factory reset’ is required for this guide, which is why you shouldn’t skip this step and apply it in order for your device to boot in normal mode.
    - the ‘factory reset’ step is listed in the tutorial and it wipes all data from system partition, while all the other internal / external sdcards won’t be affected in the process.
    - ‘factory reset’ can be skipped only in case your device already sports a previous build of CM 11 Nightly ROM, but in case it doesn’t boot, then you will be forced to repeat the entire tutorial once again and apply all steps.
  • backup SMS text messages, data from installed applications and APN Internet Settings using the following tools for Android: Helium | SMS backup & restore | APN Settings Backup & Restore.
    - root access has to be granted for these apps.
  • sync Contacts info with your Gmail account.
    - guide here for those that don’t know how to sync such data.
  • enable USB Debugging from Developer Options.
  • check the phone’s battery power and make sure that it is over 50%, so that the device won’t switch off in the middle of the installation process.
  • this is a guide for advanced users, don’t skip any steps and use the comments field to ask for more help in case you cannot complete the CM 11 Nightly install.
  • do not blame us in case the device gets bricked nor in case you lose any important data files in the process.

These were all the guidelines you had to go over before starting the installation.

How to flash CM 11 Nightly ROM for the AT&T Galaxy S3:

  1. Download the custom ROM zip from here.
    - you have to download the latest build available.
  2. Download Gapps for Android 4.4 custom ROMs from here.
  3. Connect the phone to PC, then move both zip files to its internal storage.
    - disconnect the AT&T SGS3 from PC when the files are copied successfully.
  4. Power off the Galaxy S3 now and then boot it in CWM Recovery Mode.
    - if you don’t know how to do it, then you can follow the info here.
  5. Create a NANDROID Backup for the installed ROM:
    - select ‘backup and restore’ option from the main CWM Recovery screen, name the file and confirm the action.
  6. Next, apply ‘factory reset’:
    - select ‘wipe data/ factory reset’, confirm.
    > don’t skip this step, unless you’re running the latest CM 11 Nightly ROM.
  7. Now you can flash the new custom ROM:
    - select ‘install zip from sdcard’, then ‘choose zip from sdcard’, find the CM 11 Nightly zip and install it.
    > don’t press any buttons until the process is complete.
  8. After the ROM is flashed, select again ‘choose zip from sdcard’ and then flash the Gapps zip as well.
  9. Return to the main custom Recovery screen when all the files are installed.
  10. Select ‘reboot system now’ and wait until the first boot process completes.
    > note that first boot of CM 11 Nightly might take a while to boot, which means that you shouldn’t press any buttons until you see the home screen.
  11. Enter your Google or CyanogenMod account info when the home screen of CM 11 appears, then take control over your AT&T Galaxy S3.

Now that you’ve completed all steps you should start testing all the new features. If you have any other questions regarding the installation process, then you should use the comments field below.

  • Hassan

    Im using SGSIII I747. When i want to install the CM 11 zip file on CWM recovery I am getting the following error:

    This package is for “d2att” devices; this is a “d2spr”.

    Need help!