Install Official CM 10.2 Nightly ROM build for T-Mobile Samsung Galaxy S3

Install CM 11 Nightly ROM for T-Mobile Galaxy S3

CM 10.2 is now available for the T-Mobile Galaxy S3 and you can use this post in order to learn how to successfully install it. This is an official release by the CyanogenMod team and not by Samsung, which is why you will require a rooted device for this tutorial to work with your phone.

To make sure that you manage to flash the new CM 10.2 ROM, then you will first need to take a look at the preparation guide below:

  • Use this post only with the Samsung Galaxy S3 T-Mobile variant.
  • Don’t try to update any other Galaxy S3 version with the files you find in this post, as this ROM build won’t work with it.
  • Your phone has to be factory unlocked, rooted and running a custom Recovery image like the CWM or TWRP.
  • The tutorial will ask you to ‘factory reset’ your device, which is why you need to know that the system partition will be wiped in the process.
  • The Factory Reset process will delete all files from the TMO Galaxy S3 smartphone. This is the part of your device that contains installed apps data, call logs, SMS and other similar files.
  • If you wish to backup SMS, Call Logs and APN Internet Settings use these applications for Android: SMS backup & restore | Call Logs backup & restore | APN Settings Backup & Restore. Root access will be required for some of these applications.
  • Use this info here to learn how to backup saved phone numbers by syncing them with your Gmail account.
  • This is a guide for advanced Android users, you shouldn’t blame us in case something goes wrong as in phone getting bricked or you losing any important data files in the process.
  • Make sure that there is enough power left in your phone’s battery.
  • In case the device discharges during the installation, then you will be forced to repeat the entire tutorial once again.
  • Read all the instructions and make sure that you do not skip any steps in the process.
  • If you cannot complete the update, then you can ask for more help in comments.

I think that these were all the guidelines that you had to go over before continuing to the next part of this article. Make sure that you don’t skip any steps that I have listed.

Also note that in case your device is already running on a previous build of CM 10.2 release by the CyanogenMod team officially via get.cm, then you won’t need to apply the ‘factory reset’.

How to update T-Mobile Galaxy S3 with Official CM 10.2 Nightly ROM – Android 4.3 AOSP Jelly Bean custom ROM:

  1. Download the CM 10.2 Nightly zip file from here.
    - make sure to download the latest build.
  2. Download Gapps for CM 10.2 and Android 4.3 custom ROMs from here.
  3. After the files are downloaded, connect your device with your PC.
  4. Move both zip files on your Galaxy S3 internal SDcard. When the files are copied with success, disconnect the device from computer.
  5. Power off the phone completely.
  6. Boot it into CWM or TWRP Recovery Mode. It depends on which custom recovery image you have installed on your phone.
  7. First you have to create a full NANDROID backup of the current T Mobile Galaxy S3 installed ROM.
    > for CWM Recovery select ‘backup and restore’. Select the ‘backup’ option and then create the file.
    > for TWRP Recovery press Backup, then you should select the system parts you wish to backup. Confirm the process.
    - this file will act as cover in case you don’t like the new CM 10.2 ROM or the device doesn’t boot normally.
    - in case you want to restore this backup file then you should make sure to use the same custom Recovery Mode.
  8. Now that the backup has been created you need to apply a ‘factory reset’:
    > CWM Recovery: select ‘wipe data/ factory reset’. Confirm.
    > TWRP Recovery: press Wipe, then Factory Reset. Confirm.
    - in case your device already runs on a previous build of official CM 10.2 ROM, then you can skip this step.
    - note that in case the phone doesn’t boot after you install the new ROM, then you will need to return to this step and apply ‘factory reset’ in order to force it to boot normally.
  9. Install the CM 10.2 Nighlty ROM now:
    > for CWM Recovery select ‘install zip from sdcard’, then ‘choose zip from sdcard’. Find the ROM zip file and confirm this process.
    > for TWRP Recovery: press Install. Browse your device’s internal storage, find the CM 10.2 Nightly zip file. Load it into TWRP, then slide the blue button to confirm that you wish to update your device.
    - the installation process should take several minutes to complete. Don’t press any buttons.
  10. When the ROM is flashed, you have to repeat step 9 actions to install the Gapps file.
  11. After both files have been installed, return to the main CWM / TWRP Recovery mode screen.
  12. Reboot your smartphone now into normal mode using the ‘reboot system now’ for CWM Recovery or the Reboot > System buttons for TWRP Recovery.
    - the first boot process of this new CM 10.2 Nightly ROM shouldn’t take more than a couple of minutes to complete.
  13. Enter your Google Account details when the home screen appears.
  14. Now you can begin to test all the new features and functions that have been added.

Now that you’ve managed to complete all the required files in order to get the CyanogenMod 10.2 Nightly ROM successfully installed on your TMO Galaxy S3, then you can begin to customize the entire device looks and performance settings.

If you have any problems installing this new ROM, then you should ask for more help in comments, as we will try to offer you a viable solution and help you update your device.

In case you don’t like how your Galaxy S3 T-Mobile runs with the CM 10.2 Nightly ROM installed, then you can restore it to its previous ROM using the backup file created in step 8. Use the same custom Recovery Mode.

If you think that your phone’s performance has been improved, then you should know that you can keep updating the ROM using the Settings menu, then opening CyanogenMod Updates menu. Check for new versions of the CM 10.2 Nightlies and click once to download and install all the required files that you need in order to run the latest CyanogenMod 10.2 ROM on your Galaxy S3 smartphone.