Recently we saw the Android 4.1 Jelly Bean based MIUI ROM released for the international Galaxy S3, and now it is available for the AT&T Galaxy S3, thanks to a port by XDA Forum Member Tejh.

Owners of other variants of the Galaxy S3 can find links to Jelly Bean custom ROMs at the bottom of the article.

MIUI is a custom ROM with a unique interface and with other features such as an intuitive status bar, its own home-brewed apps such as a home launcher, music, contacts, messages etc, privacy protection, inbuilt themes manager (with scores of fan-made themes available) and further under the hood tweaks for one of the best and unique experiences on Android. And of course you also get Jelly Bean, the latest and greatest version of Android.

Keep in mind that this is not an official Samsung ROM. It’s a custom ROM that is under development and may have a few bugs and issues, and some things may not work properly and some stock Samsung ROM features will not be available.

The ROM currently has the following issues as of 28-08-2012 (quoted from the source page where the most updated list of issues can be found):

Issues:

Screen Flickers :: FIX – Disable HW Overlays
Keyboard doesn’t show up :: FIX – go to Language & Input and disable HW keyboard
MMS Doesn’t work :: FIX – Go to APN settings, click the ATT LTE APN, change Authentication Type to none and viola!

Let’s take a look at how MIUI ROM can be installed on the AT&T Galaxy S3.

Compatibility

This guide below is compatible only and only with the AT&T Galaxy S3. It’s not compatible with any other Galaxy S3, it only works for AT&T variant. Check your device’s model in Settings» About phone.

Warning!

The methods and procedures discussed here are considered risky and you should not attempt anything if you don’t know completely what it is. If any damage occurs to your device, we won’t be held liable.

How to Install MIUI Android 4.1 ROM on AT&T Galaxy S3

  1. This procedure will wipe all your apps, data and settings (but it will NOT touch your SD cards, so don’t worry about those). Backup your Apps and important data — bookmarks, contacts, SMS, APNs (internet settings), etc. This Android backup guide would help you.
    NOTE: Don’t forget to at least make a backup of your APN settings, which you can restore later if your data connection does not work after installing the ROM. Use the backup guide to find out how.
  2. Install ClockworkMod recovery on your phone by following the guide → here.
  3. Download the latest version of the ROM from the source page.
  4. Copy the downloaded zip file from step 3 to the internal SD card. Do not extract them.
  5. 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.
  6. 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.
  7. Select wipe data/factory reset, then select Yes on next screen to confirm. Wait a while till the data wipe is complete.
  8. 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 – Install _____.zip on the next screen. The ROM will start installing.
  9. After the ROM finishes installing, select go back then select reboot system now to reboot the phone into MIUI ROM.
  10. Be sure to read the list of issues at the top of the article to know how those issues can be fixed.
    NOTE: If you want to go back to your previous ROM, boot into recovery (like you did in step 5), select backup and restore then restore your previous ROM by selecting it from the list.

MIUI ROM, based on Android 4.1 Jelly Bean is now installed and running on your AT&T Galaxy S3. Visit the official development page for more info and to get the latest updates on the ROM. Share your thoughts on the ROM in the comments.

Try out some other Jelly Bean ROMs for the AT&T Galaxy S3 → here.

Jelly Bean ROMs for other Galaxy S3 variants: