If you are with the US-based phone carrier AT&T you can manually update to this version of Android 4.4.2 KitKat namely I747UCALG1 firmware. As you can see in the name it contains the S3 model number I747 and that’s because it is the only device it is made for. Do not try to install this on another variant of the S3 or any other smartphone for that matter because it can soft-brick the handset.

What we have here is the official firmware distributed and signed off  by Samsung and AT&T; therefore you will lose any root access that was previously reinstated. The good news is that it can come back afterwards as long as you don’t mind voiding the warranty. If the warranty was previously void before now because you had a custom Rom running, then it will be working again. Just remember that in most countries a warranty doesn’t last forever and just because you paid for one doesn’t mean that it isn’t out of date. Looking at the age of this handset it’s unlikely anybody still has anything left anyway, so there’s nothing to worry about.

Samsung Galaxy S3 AT&T

The stock ROM we have here today works by using cache.img, factoryfs.img, hidden.img, modem.bin and various other files such as zImage and sbl.bin.

Checklist

Don’t start unless you have the Samsung USB Drivers up to date and enable USB Debugging mode. To enable it go to apps > Settings > Develop Options > USB Debugging > OK and it will turn on and work. Now we can connect to the computer system Unit and everything will be fine.

Flashing stock Android firmware for Samsung-based smartphones and tablets is done by using a tool called Odin. The Odin app is made by the real Sammy developers and they only catered for Windows-based PCs and the operating system ranging from Windows XP, Vista, Windows 7 and 8. There is a Windows 9 ready to release just around the corner but as of now it isn’t compatible yet.

The S3 batter offers 22 and a half hours talk-time and 34 and a half days stand-by time. The capacity is 2100 mAh and it does have wireless charging as an optional feature. What does all that mean? The battery is pretty darn good and can last, but because of the age and ware it’s seen it won’t last as good as it once did for most people who have used the smartphone for a long time. The point being, please make sure the battery doesn’t turn off during the guide and it does have enough power to see it through to the end.

As I previously mentioned, it will work for any of the above operating system versions, but I recommend using nothing pre-Vista if you want to save the files to your C: Drive. If you use XP located files is not as easy because you can’t type the file name into the search bar and pull it up as easily; therefore I recommend saving the files to the desktop from XP and deleting them into the recycling bin when you are finished with the guide.

Security applications can get in the way so we like to disable them temporarily for now until we finish. Turn off any antivirus program running on the Windows OS and also the Android OS. These days it’s common for people to use antivirus protection on the mobile device in the form of an app.

The Galaxy S3 comes with 32 GB of built-in storage space and if that isn’t enough people can buy a further 64 GB’s of space using microSD, microSDHC and microSDXC storage solutions.

Backup the market app, call logs, SMS text, MMS messages, photos, contacts, videos and music files from various artists that you listen to by using the internal or external storage options. If you don’t want to use those options try checking out Google Drive, a Google cloud storage service that is currently offering up to 15 GB of free space in the cloud for anyone who signs up using an Android-based OS. Furthermore, people can navigate over to the Google Play store and pick up a copy of the helium app, Titanium app or backup by taking a NANDroid backup if on root access.

If we go back two years in time there is another firmware with the same name from the same device and carrier. It’s not understood why they chose to use the same figures and frankly its confusing. Put it down to a mishap, but the important factor to notice here is that we are talking about the new Android Kitkat update here and that was not around back in 2012. That’s how it is easy to identify the difference for you guys. If you have any questions or are confused by something, please leave a comment or get in contact using the tab above and we’ll talk with you and sort everything out.

How To Update The Samsung Galaxy S3 For AT&T Subscribers With Android 4.4.2 I747UCALG1 Official Firmware

1. Download the zip file namely I747UCALG1 here.
– extract the contents to the destination of your choice.
– popular choices are the desktop and the C: Drive.
– the choice will depend on whether you plan on keeping the file long term or short term.

2. Download the latest Odin 3.09 here.
– the direct link is available on the first page.
– if you already have Odin then there’s no need to download it again as long as it’s the correct version.

Have the Odin application open and running on the desktop.

3. Boot the smartphone in Download Mode.
– press and hold the Home + Power + Volume Down keys.
– wait for the Android logo.

4. Fetch the USB cable.
– it likely is sitting where you charge the phone because it’s the same wire.

5. plug one end into the computer system unit and the other in the phone.
– each end is unique so it can only go one way.

6. Look for the ID: COM port turning blue and an “added” message showing up on the screen of the PC.
– if it doesn’t happen re-download the USB drivers and check that they are the up to date edition.

7. Click the AP or PDA button in Odin.
– generally the latest version shows us the AP option.

8. Upload the tar.md5 file to the location and wait until the file extension shows up.

9. Do not check the re-partition box.

10. Make sure the two default settings are turned to the on position.
– they are Auto reboot and F Reset Time.

11. Click the start button to begin the flashing when you are ready.
– it can take several minutes to complete.
– the first-time boot after it reboots itself can take some minute also.

12. Close down Odin when you are finished.

13. Visit the “safely remove hardware” icon from the Windows system tray and stop the USB Mass Storage device.
– now the smartphone is OK to disconnect from the PC and you can enjoy the new software update.