Update Galaxy S3 I9300 to Jelly Bean 4.3 via Carbon AOSP Custom ROM

Carbon AOSP custom ROM not only works with Samsung’s Galaxy S2 I9100, but also with the manufacturer’s Galaxy S3 I9300.

As was the case with the other phone we covered, this model will also get the full flavor of the Android 4.3 Jelly Bean. To enjoy this Android version on your phone, you will have to perform our tutorial.


In the beginning of things, you should notice the following requirements and do as they say:

  • look for a rooting tutorial and apply it on your smartphone;
  • look for another guide, this time on how to correctly flash a custom recovery on your phone and follow it;
  • use a factory unlocked model;
  • turn on USB Debugging on the Galaxy S3 GT-I9300 (first go to Developer Options and from there enable that option);
  • make a normal backup via these instructions and then create a NANDroid one;
  • go to your Google Mail account and sync the info on your Contacts list;
  • perform a Factory Reset on the handset;
  • look at your smartphone’s battery and, if it’s empty, charge it.Galaxy-S3-GT-i9300


  1. The first couple of guidelines that must be done in order to start the update look like this: download and Gapps on your notebook. Then leave both of these 2 packages unzipped and just connect the handset to the laptop or PC by way of the phone’s respective USB cord.
  2. The Google Apps and the custom ROM file have to be moved from where they are to the usual SD card root of the Galaxy S3 I9300. Then you will have to unplug the handset from your notebook and switch it off after that move.
  3. Boot your smartphone in Recovery Mode next, then make that NANDroid backup if it hasn’t been created for the pre-requisites. The steps to follow in case TWRP is on the device: after you tap “Backup“, you should confirm the process after you are done choosing the files you feel like saving.
  4. However, if the Galaxy S3 I9300 has CWM on it, you need to select “Backup & Restore“, choose “Backup to internal SD card” and confirm.
  5. You should now apply, according to the custom recovery image, a Factory Reset. To do so for a TWRP phone: tap “Wipe” and confirm once you’ve tapped “Factory Reset“. In the case of the CWM: choose “Factory Reset/Wipe Data” and confirm this.
  6. When you have finished with the latest steps, you should learn how to install Carbon AOSP on your phone. To do that for your phone that sports TWRP, you need to tap “Install” first, then look for the file, have it loaded in the custom recovery and then begin the flashin by swiping a button found at the display’s bottom.
  7. [sc name=”banner-jos”]If, however, you have the CWM on your handset, you should tap “Install zip from SD card“, opt for “Choose zip from SD card” and confirm the flashing of the Carbon AOSP Jelly Bean 4.3 custom ROM after you find it.
  8. Then install the Google Apps by using the same tactics which helped flash the previous upgrade file.
  9. The handset should now sport the update firmware. If there’s no way you like it, do as follows to enjoy the old ROM: restart your smartphone into a Normal Mode.