Install CM12 ROM on Samsung Galaxy S3 Neo (GT-I9300I & GT-I9301I)


With Android 5.0 Lollipop covering the whole Android community and a large lot of devices, custom firmware manufacturers have laid down their hands at work to enter the showdown as soon as possible. CyanogenMod is one such custom firmware crafter who have started their work and is continuously working hard for the first release of CyanogenMod 12 to the public. While operating, the team has already pushed major bits of their newly built code to their git for the world to track and contribute. Whilst, developers at XDA have also begun and compiled this beautiful piece of work for their devices.

One such amazing device is the Samsung Galaxy S3 Neo, which is the Qualcomm variant of the amazing Galaxy S3.  It runs on a Snapdragon 400 1.2GHz quad-core Cortex-A7 processor, with an Adreno 305 GPU, 4.8-inch Super AMOLED display and a few other improvisations, plus it also comes with Jellybean 4.3 out-of-the-box and is upgradable to KitKat 4.4 officially.

While there has been no word from Samsung about future updates regarding the device, Rox (Senior Member – XDA Forums) has shown his gratitude and compiled CM12 ROM for Samsung Galaxy S3 Neo GT-I9300I and GT-I9301I, from the source. The first version itself came out on 24th of December, but before that was the contributed hard work of our fellow developer, to fix the bugs and clear the ROM for a better user experience. The current build is labelled as Stable, but consists of some minor bugs (list below), which are assured to be fixed in the near future. In general, CyanogenMod is itself working very hard matching with Android 5.0 Lollipop’s source code. A few things that you will be observing in the builds are:

  • AudioFX
  • AOSP Browser
  • CM File Manager
  • New and improved Messaging app
  • Music Player with material interface and extra features
  • Dialer tweaks
  • Sound Recorder
  • Brightness control
  • Quick pulldown
  • Notification count
  • Battery style and Battery percentage
  • Left-handed mode
  • Power button end call
  • Volume button tweaks
  • Ambient display
  • Double-tap to sleep
  • Wake on plug
  • In-built color calibration
  • Increasing ring volume (Ascending ringtone)
  • Notification and Battery light modifications
  • CM System profiles
  • Privacy settings (Blacklist, Privacy guard, Notification filter)
  • Trebuchet launcher
  • CM Wallpapers

Apart from these, CM12 has tons of tweaks within, which makes it a remarkable ROM. View the concerned XDA thread for more information on this ROM and participate in the discussion with other ROM users.

Confirmed Bugs

  • Call Audio in secondary SIM (GT-I9300I)
  • Non-working camera for some devices (Fix available)
  • Near Field Communication (NFC) not working

Before You Begin

  • Backup your device completely.
  • Charge your Galaxy S3 Neo to at least 60% battery level.
  • Keep USB Debugging enabled. It has nothing to do with ROM flashing but it might prove helpful in case of some mishap.
  • Root and install TWRP on your Galaxy S3 Neo using our guide: Link


ROM: Link

GApps: Link

Fix (non-working camera): Link

Install CM12 ROM on Samsung Galaxy S3 Neo

  1. Download the ROM, GApps and Fix (if any) zip files.
  2. Connect your Samsung Galaxy S3 Neo to the PC via USB cable, in MTP mode.
  3. Transfer the downloaded zip files to the root directory of your device’s external storage.
  4. While the device is connected, open a command prompt window and type in the command below to reboot directly into TWRP mode, or you can also follow the manual drill by pressing the required buttons to reboot into recovery mode.
     adb reboot recovery
  5. Once you have entered the TWRP recovery and see its main screen, its time to install the ROM.
  6. Before, you start the flashing procedure, you need to wipe the current partition or in simple words – remove the current ROM.
  7. To do this, tap on Wipe, go to Advanced Wipe and check the System, Data, Cache and Dalvik-cache boxes.
  8. Now, swipe the button on the bottom of the screen to start the wiping procedure.
  9. Now, go back to the TWRP main screen and tap on Install.
  10. Browse to the location where the downloaded files were placed and select the ROM zip file.
  11. Install the ROM and when it’s flashed, go back and tap the Install button again. This time, select the Google apps package and install it too.
  12. Following the same step, also add the fix zip file to the flashing list.
  13. Swipe the button on the bottom of the screen to confirm and begin the flashing process.
  14. It will take a bit of time and once done, tap on Reboot > System.

The first boot might take some time, so just sit back and let it do its job. We have successfully installed CM12 ROM on Samsung Galaxy S3 Neo GT-I9300I & GT-I9301I. You might feel some features to be incomplete or minor hiccups, that’s because the CM code is still not complete. The stability will improve with every new build that comes out, give your appreciations to the developer for contributing to the Galaxy S3 Neo community.

Comment below and provide us with your valuable feedback, and help us build a better community.

  • Saad Rahman

    bro its work on android 4.3????
    reply fast bro….

  • June Rey Yanoc

    good day mr developer, i have problem with the google camera, it says camera error, i flashed the camera fix you’ve posted but still it didn’t worked, i’d be glad if you could fix this thank you

  • Yes.


    supports Greek language?

  • Alexandru Grigore

    Not the last one, the one with 16k downloads..

  • Did you install the latest CM ROM?

  • Alexandru Grigore

    Hi there! My camera still doesn’t work..What should i do?

  • hopeton

    Hi Rakesh, I need ur assistance asap please. After trying to install the TWRP on my phone, it is now stuck on the samsung logo and not turning on. I put it in recovery mode but i am getting ‘team win’ recovery, I am not seeing the samsung recovery.

  • hopeton

    hi rakesh cant find gapps,could you sen me a different link

  • hopeton

    Hi rakesh didn’t get a response. Your help would be appreciated . Thanks

  • hopeton

    Never root my phone before

  • hopeton

    Could you send me a video how to do this

  • hopeton

    Hi rakesh. I tried to install root but every time it try am getting 0 fail

  • hopeton

    rakesh i tried to install root permission but am getting all thread completed 0 failed

  • hopeton

    Ok thanks man. Will let you when am finished

  • Just copy them as they are.

  • hopeton

    Hi rakesh thanks for the quick response. One more thing, do I unzip supersu file and the Knox removal script or should I just copy it to the phone?

  • Kemal Mulic

    Failed to install ROM ?
    Please help
    Error flashing zip

  • Alex Greece

    It works but its very laggy!

  • Angel gomariz lozano

    Please fix the NFC

  • Angel gomariz lozano

    fix the NFC which is useful and I use it quite
    Please fix the NFC

  • Sasha|FlipThaGames|

    My Camera still doesn’t work and i did flash the camera fix, rom works fine on s3 neo

  • No, it’ll not,

  • Oussama Sayém

    thanks ,
    is this phone will gets ofiicial lollipop ??

  • Marios

    I tried it but now it fails to install the ROM!

  • Reboot to TWRP, wipe cache, data, system, install the ROM and then flash the Gapps.
    Do it again.

  • Marios

    I followed the steps above when i make the final reboot my phone stucks at booting! I have I9301I

  • John Barry Navarrete

    I downloaded the latest ROM. The march release

  • John Barry Navarrete

    While at TWRP, I’ve wipe all the caches and all, and I am at the process of installing the rom after swiping to install I get a “failed” message. Can you please help?

  • What error did you get and which ROM you downloaded?

  • John Barry Navarrete

    Please help. I followed all the instructions carefully, but it says that it failed to flash the rom. I installed the latest one.

  • Try the latest ROM:

    It’s more stable.

  • Angel Gomariz

    Hi I tried the latest version of cyanogenmod 12 for my i9301i with the arrangement of the camera and still does not work I can do anyone know how you can fix or when it fixed in the next update

  • Try some other ROM then.

  • Ahmad Husni Elyyan

    my battery drains very quickly on This rom … plz help

  • You must have wiped system partition without installing the new ROM. Copy the ROM file on the external SD and install the ROM.

  • prabhav

    when i install rom , the recovery restarts. please tell me what to do because my system is wiped

  • sunil

    how to tack screenshot in cm12. s3 neo