[Galaxy S III General] jbonetwo:
The Galaxy S3 being my first android (or smartphone for that matter), I had a tough time trying to figure out how to root my phone, which methods to use and which ROM to install. So I've compiled this from other threads here on xda after 2 days of heavy reading, for other noobs like me :cool:

FOLLOW THIS GUIDE TO THE LETTER. DO NOT TOUCH ANYTHING, PRESS ANYTHING, CHECK ANY BOXES UNLESS TOLD TO DO SO OR YOU WILL END UP WITH A 600$ BRICK

[/COLOR]Rooting

So what is rooting? Rooting basically gives you administrator privileges on your phone, allowing you to install a host of programs that allow you to, for e.g. use firewalls, remove bloatware, change themes, install improved kernels, install custom roms with improved boot and memory performance, the list is really endless.

ROOTING VOIDS YOUR WARRANTY

However, it IS possible to reverse the process and cover your tracks, should you need to claim warranty. Read on to find out how.

Here is some good prereading to help you understand the basic flashing process and apps involved, even if it was written for the S2:

http://xdaforums.com/showthread.php?t=1125282

Before we begin, its a good idea to note down the details under Settings -> About Phone, for future reference. Also note that under Status, if you root your phone, it changes to 'Modified'. This is, as stated before, reversible.

This guide is for the GT-I9300 Model. If your model number has a suffix (other than T) this may not work.

Step 1: Flashing CF-Root with Odin

This is an easy method to root your phone and I haven't needed to use any other. It comes with the added benefit of also installing Clockwork Mod and CWManager which we will use to make backups, flash our first ROM and cover our tracks. For those of you who want to install the newer clockworkmod touch look here:

http://xdaforums.com/showthread.php?t=1719744

Guide compiled from here:

http://xdaforums.com/showthread.php?t=1695238

1. Install Samsung Kies and plug your phone into your PC via USB so that all the appropriate phone drivers are installed

2. Download and extract Odin3-vX.X.zip from the download link below

3. Download and extract CF-Root-SGS3-vX.X.zip ONCE (you will end up with CF-Root-SGS3-vX.X.tar

CF-Root for SGS3 v6.4:

http://download.chainfire.eu/196/CF-Root/SGS3/CF-Root-SGS3-v6.4.zip

4. Disconnect your phone from your computer, close Samsung Kies and any antivirus/firewall that may interrupt the flashing process

5. Run Odin, click PDA and navigate to your CF-Root-SGS3-vX.X.tar file

6. Power off your phone and then boot it into download mode (Hold Volume Down + Home + Power button until the screen fires up)

7. Note the warning and continue.

8. Connect the phone to your PC via USB and allow drivers to install.

9. Make sure 'Re-partition' is NOT checked in Odin

10. Click Start button and wait for android to boot

11. If you see a green 'PASS' message in Odin, everything went as intended. Done!

Step 2: Make a NANDroid Backup

This is a precautionary measure that backs up your phone's current state, should you have any problems with custom Roms. It is also a step in reversing the root process, should you need to claim warranty.

1. Power off your phone and boot into recovery mode (Hold Volume Up + Home + Power button untill the screen fires up). This starts up ClockworkMod.

2. Use Volume Up/Down to navigate and the Power button to select

3. Navigate to Backup/Restore->Backup and wait for backup to finish

4. Go back and select 'Reboot System Now'

5. Connect your phone to your computer and copy the backup folder from /sdcard/clockworkmod/backups/

6. Done! Now you can restore this backup by booting into recovery mode and hitting Restore!

Step 3: Installing your first ROM

After hunting for a good ROM that was fast and bloatware free, I ended up with the nightly build of the popular CyanogenMod 9 and I don't intend to go back!! I haven't had any problems with it whatsoever but if you prefer, you could instead install the RC version.

Note: The camera's flash feature cannot and will not work on any version of cyanogenmod until samsung releases source code for their camera.

Here's how to flash the ROM. This is also the basic method of installing any other ROM or kernel, though the ROM/kernel developer would give you more tailored instructions.

1. Download the desired version of CyanogenMod 9 from here:

http://get.cm/?device=i9300

2. Download Gapps from here. I used the 20120429 version. This may not be necessary for other roms.

http://goo.im/gapps

3. Copy both files to your phone's internal sd card

4. Boot into recovery mode

5. Select 'wipe/factory reset' and confirm

6. Select 'wipe cache partition' and confirm

7. Go to Advanced -> wipe dalvik cache and confirm.

Now we're ready to flash the ROM!

8. Select 'install zip from sd card'

9. Select 'install zip from internal sd card and navigate to the cyanogenmod file and confirm

10. When done, use the same method to install the gapps file

11. Do a wipe/factory reset again (needed for google calendar sync to work)

12. Go back and select 'Reboot system now'

13. The boot screen of the new ROM will show up. Wait about 10 seconds, remove the battery and put it back in.

14. Power on and setup your phone. Done!

More on CyanogenMod:

http://xdaforums.com/showthread.php?t=1714354

Step 4: Installing your modem

With CyanogenMod 9, people report that the first call made doesn't work, but every subsequent call will. If, however, you are still unable to make calls, you may have to install your phone's specific modem driver which you should have noted under Baseband version before we began (under Settings->About Phone).

1. Go here to download your specific modem and copy it to your phone's internal sd card:

http://xdaforums.com/showthread.php?t=1740061

In my case, it was XXLFB.

2. Boot into Recovery Mode

3. Install .zip from internal sdcard and navigate to your modem.zip file

4. Done!

Step 5: Covering your tracks

So your phone is broken and you need to claim warranty? Not with your rooted phone you don't! The S3 uses a flash counter that tells it how many times the phone has been flashed, and your rooted phone appears as 'modified' under status information. Here's how to cover your tracks.

1. Download your phone's stock firmware for your region from here and copy it to your phone

http://www.sammobile.com/firmware/?page=3

2. Download TriangleAway from the download link below or consider buying it from googleplay to support the hardworking developers, extract it and copy it to your phone:

http://xdaforums.com/showthread.php?t=1494114

3. Install TriangleAway by opening the .apk your phone's file explorer (Mine's ES File Explorer)

4. Run TriangleAway and select 'Reset Flash Counter'. Your phone will Reboot into a special mode. Reset the flash counter here and pull the battery immediately after reboot.

5. Boot into Recovery Mode and do a factory reset, cache wipe and dalvik cache wipe.

6. Flash the stock Firmware, reboot and setup the phone without any logins.

7. Check that Settings -> About Device -> Status is not 'Modified'

8. Done!

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More on TriangleAway:

http://xdaforums.com/showthread.php?t=1494114

Optional: Upgrade to CM10

1. Make a Nandroid backup so you can restore if you dont like cm10/if its too buggy.

2. Download CyanogenMod 10, Gapps and your modem from here and copy it to your internal sd card:

http://www.clockworkmod.com/rommanager/device/i9300/developer/daniel.hillenbrand%40codeworkx.de?manifest=http%3A%2F%2Fdeveloper.clockworkmod.com%2Fdeveloper%2Fdaniel.hillenbrand%40codeworkx.de%2Fmanifest&name=codeworkx&deviceName=Samsung%20Galaxy%20S3

3. Boot into Recovery Mode and install cm10 then gapps then modem using 'install zip from sd card -> choose zip from internal sd card'

4. Do a factory reset/wipe then reboot

5. Done!

More on CyanogenMod 10:

http://xdaforums.com/showthread.php?t=1779578

Please point out any errors/suggestions so I can make the appropriate changes. Also report any issues for the benefit of other noobs out there

Admins: If my formatting is inappropriate I apologize but I'm by no means an expert at this

Credits:

Chainfire

Teamhacksung

willk22

UpInTheAir

and All contributors without whom none of this would be possible

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