After giving a teaser that CyanogenMod 10.1 (CM10.1), based on Android 4.2 Jelly Bean, was coming to the Galaxy S3, CyanogenMod developer codeworkx has finally released it for everyone to take for a spin, so they can get to enjoy all the features of Android 4.2 right now, instead of waiting for the official update, which will no doubt come some time next year.

However, the initial word we heard on the ROM noted some major issues in the ROM, and I’m afraid the list of known issues even right now is quite big and lengthy. The UI is laggy, mostly due to Samsung’s poor implementation of Project Butter and their hardware drivers, Bluetooth is glitchy, and a few more things, all of which are listed below, quoted from the source page.

Known Issues (as of December 8 2012)

  • UI: lags, tearing, glitches
  • UI: Apps like NHK are broken
  • UI: Black screen on Phone app. Don’t do phone calls.
  • Camera: Recording effects broken
  • Camera: Touch 2 focus issues with enabled flashlight
  • Bluetooth: audio streaming sometimes becomes laggy or stops at a distance > 1m
  •  FM Radio: unsupported
  • TV Out: unsupported, will never work (proprietary, undocumented)
  • Lots of missing and yet unimplemented features
  • and a lot more

However, knowing the brilliant mind of codeworkx and other developers that work on Samsung devices, most of these issues should be on their way out of the known issues list quite soon, and if you’re coming to this article a bit late, you can check the source page to get the most updated list of known issues.

To try out CM10.1 on your Galaxy S3, follow our step-by-step guide below and you’ll have it up and running on your phone in no time, though remember that right now, it’s more of an experimental ROM than something that can be used as your main ROM. Also, since this is a ROM based on stock Android instead of Samsung’s firmware, you won’t find most of the special Samsung features, including but not limited to some apps not being the same, such as the camera or gallery app.

Let’s take a look at how to install CM10.1 on the Galaxy S3.

Compatibility

This guide below is compatible only and only with the international version of the Galaxy S3 – i9300. It’s not compatible with any other variant of the Samsung Galaxy S3. Check your device’s model in Settings » About phone.

Warning!

The methods and procedures discussed here are considered risky, so try them out at your own risk, and make sure to read each step carefully before attempting anything. We will not be held responsible if anything goes wrong.

How to Install CM10.1 on Samsung Galaxy S3

  1. [Important] The procedure to install the ROM includes wiping the data on the phone, so make sure you backup important apps and data such as SMS, contacts, bookmarks, etc. See our Android Backup Guide for help. The personal files on your SD card, however, will not be wiped, so there is no need to back them up. You just need to take a backup of the installed apps and data such as messages if you want.
  2. You need to have ClockworkMod recovery installed on your Galaxy S3. If you don’t have it on your phone already, install it by referring to this handy guide here.
  3. Download the latest version of the ROM from the source page.
  4. Also download the Google apps package for CyanogenMod 10.1 using the link below. AOSP ROMs like CyanogenMod do not contain Google apps like Gmail, Talk, YouTube, Search, etc by default, so you will need to install the Google apps package as well.
    Download Google Apps
  5. Copy the downloaded zip files from step 3 and step 4 to the internal SD card. Do not extract them
  6. Now, boot into ClockworkMod recovery. To do that, turn off your phone. Then, hold down Volume Up, Home and then the Power buttons together until the screen turns on, then let them go. The phone will boot into ClockworkMod recovery in a few seconds. In recovery, use the Volume buttons to scroll up/down and the Home button to select an option.
  7. Perform a Nandroid Backup of your existing ROM, so that you can always restore it from recovery if something does not work out with this ROM. To perform a backup, select Backup and Restore –> On the next screen, select Backup again. Go back to main recovery menu after backup is complete.
  8. Select wipe data/factory reset, then select Yes on next screen to confirm. Wait a while till the data wipe is complete. This will not delete any of your personal files on the SD cards as those are stored on the /sdcard partition. The factory reset option only wipes the /data partition, which is separate.
  9. Select Install zip from sdcard, then select choose zip from sdcard. Scroll to the ROM file on the SD card and select it. Confirm installation by selecting Yes on the next screen. The ROM will start installing.
  10. After ROM installation completes, select choose zip from sdcard again, then select the Google Apps file to install the Google apps package.
  11. After the Google apps package finishes installing, select Go back and then select Reboot system now to reboot the phone into CM10.1. The first boot can take up to 5-7 minutes. If the phone doesn’t boot up even after 10 minutes, remove its battery, re-insert it, boot into ClockworkMod recovery, repeat step 8 to wipe data, and reboot the phone again.
  12. Updating to newer versions of the ROM: The ROM will get regular updates as development goes on, so to update to newer versions, download the ROM, copy it to the device, reboot to recovery, repeat step 9 to install the update, then reboot again. You do not need to install the Google apps package or wipe data when updating to a newer version, those steps are only required when installing the ROM for the first time.

NOTE: If you want to go back to your previous ROM, boot into recovery (like you did in step 6), select backup and restore, then restore your previous ROM by selecting it from the list.

CM10.1 is now up and running on your Galaxy S3, and you can enjoy the fruits of Android 4.2. Enjoy, and don’t forget to check the source page for updates and further details on the ROM, as well as to report any bugs you may encounter.