Everything described here is risky. You can render your phone useless by rooting it or installing a third-party operating system, and you do this entirely at your own risk.
Over the last couple of years, I’ve read about “rooting” an Android mobile phone, but was scared of being left with a brick. However, my Samsung Galaxy S3 was hardly worth saving, once I’d got my new phone. The USB port was buggered, and everything on it took place at snail’s pace.
I did a factory reset, but there was still no way of removing all the bloatware. So although I now had a phone that would work, there were few apps on it that I would want to use.
Another problem was the fact that the USB charging socket was in poor condition, and, as I had a new phone, I didn’t want to spend upwards of £30 getting it replaced, especially as I have an external charger and a spare battery.
Now if you can find an unused Samsung Galaxy S3 still boxed, you can root it using a whole number of programs, towelroot, framaroot, etc. Just download them straight onto your phone and off you go! But these worked by exploiting an error in the software that runs the phone, and this error was closed in August 2014, so if you’ve been keeping your phone updated, they’re not going to work.
If you can see the Model Number as on the illustration, it will be suitable for what I am about to describe. For many other Galaxy S3 models, this will work, but there are alternate files which will which you should download. On my phone, the Kernel version was dated August 2014, which meant I did not have the option of rooting the phone without connecting it to a computer.
Cleaning the USB Socket
This is only necessary if you are having difficulties making a solid connection through the USB socket. Before you attempt this, switch the phone off and take out the battery.
What I did was to use some strong clear alcohol (I used Bulgarian Rakia, but strong Vodka will do), with some cotton wool to clean the socket. Make sure the cotton wool is soaked before you use it to push the alcohol into the USB socket, else you’ll leave bits of cotton wool behind, and that will probably make it even worse. Having got the alcohol in, I used a toothbrush, eventually this dirty old bit of fluff came out of the socket! Leave it to dry for at least 10 minutes, longer if it’s damp or cold, before replacing the battery!
It was still not perfect, and the problem was that there was only one USB lead I had which would stay connected, and that happened to be the one that had just come with my new phone. But one is enough!
Set up USB Debugging on your phone
On Samsung Phones, you need to go into Settings > More > About and tap on the Build Number (see picture above) about 10 times. This will open up a new menu item “Developer Options”. Go into this new menu, and enable USB Debugging. Now the phone is ready to install TWRP.
Heimdall and TWRP
The first thing is to install Heimdall on your computer, then you use that to install TWRP (Team Win Recovery Project) on your phone. Note that Heimdall only works with a number of Samsung phones.
If you are running Linux, check that Heimdall is in the repository of your distribution. If it is, install it. Otherwise, and for Windows and Mac, go to this site: http://glassechidna.com.au/heimdall/ the links are at the bottom of the page. Install it.
Now go to this page for TWRP: https://twrp.me/Devices/. In the device search box, only add “i9300” not the GT- at the beginning. If your Model Number was different, try that instead. Download the version of TWRP for your precise model. I ended up on this page, and the top link was the latest. Create and send it to a folder that you can find later. I used ~/Downloads/GalaxyS3 on my Linux computer. On windows maybe it would be C:\Downloads\GalaxyS3. As for MAC, I haven’t a clue!
Superuser, CyanogenMod and OpenGapps
You’ll need to download superuser.zip just click on the link.
Now you have a choice of which Android version to use, cutting out all the Samsung bloatware. I have gone for CyanogenMod, you need to go to their page and scroll down until you find your precise phone. It’s in alphabetical order, so be patient! And once installed, you’ll need to add Google Play and one or two other essentials, else you won’t be able to add more apps. So you need to also download Open-Gapps, available at Opengapps.org — for the S3 models you’ll need to select ARM, 4.4 and nano. Then click download.
Congratulations, you now have all the files you need on your computer. The next job is to get them installed on your phone.
Backup Personal Data from your Phone!
You may lose data from your phone here, so think about what you want to save. Photos, Videos, SMS texts, for example. Transfer them to your computer. As for apps and passwords, you will probably have to re-install them. If you don’t know how to do that, you shouldn’t be rooting your phone! Remove any memory card from the phone.
Various Screens from your Galaxy S3
You get the System Recovery Screen, by switching off the phone, then holding down the Volume-Up key on the left, and the Home key and then pushing the Power Key on the right. When something seems to be happening, release the Power Key first, then the other two. You can move the bar using the Volume Up/Down keys. It might be a good idea to do a factory reset while you’re here, then reboot the phone. Of course, if you’ve taken your SDHC memory card out first, you won’t lose anything on it.
You get this warning screen on the left, by holding down the Volume-Down key, the Home key, and then pushing the Power Key on the right. You release the Power Key first like before. Although it seems to suggest dire problems if you press the Volume Up key to continue, don’t worry. If you don’t actually download anything from the computer, you can return the phone to normal by taking the battery out and putting it back.
Now on your right, what you get when you hit the volume up button from the earlier screen. Your phone is ready to have new software installed via the USB socket. So you’ve backed up whatever stuff you need to keep, you’ve taken out the SDHC memory card, and the SIM for now, you’ve downloaded your programs, you’ve installed Heimdall, and you have a nice tight fitting USB lead ready to connect to your computer. You’ve also fully charged the phone, as you don’t want the battery going flat in the middle of all this! Well, here we go. Get your phone into Download mode, and use the USB lead to connect it to your computer.
Now Open A Terminal
Run your command or terminal program. In Windows it’s a command terminal. In Linux it’s a terminal. Probably in Mac too. The prompts are different, and the slashes face opposite ways, and the first thing you have to do is to go to the folder you saved all your downloads in. Using the examples from earlier:
- Windows: Type “cd C:\Downloads\GalaxyS3” (without the quotes)
- Linux (and I think Mac, too): Type “cd ~/Downloads/GalaxyS3”
In Linux, you need “root authority” in order to make Heimdall work, so, depending on which version of Linux you are using, you need to type:
- su, then hit ENTER, then put in the root password.
However if you are using Ubuntu or one of its derivatives, then instead, you just need to add “sudo” to the start of every line before “heimdall”, and put in your own password. I’ve not included the sudo in the lines below, so remember it!
The first thing to do is test whether there is a connection between the computer and the phone:
- heimdall detect (then hit Enter, as in every one of these lines).
The computer should reply with “Device Detected”. If it doesn’t, check everything, is in place, and maybe try a different USB lead. Once you get the reply you want, you need to type this:
- heimdall print‑pit
If this completes without error, then you’re good to go. The phone will return to its normal mode, and you’ll have to turn it off, and start it again in Download mode. Before you restart the phone, disconnect it by removing the plug from the computer’s USB port. If you’ve had a nice snug fit at the phone end, don’t disturb it! OK so you’re back in download mode, and plugged back in to the computer.
- heimdall detect
Just to make sure! Then, and here’s the biggie….
- heimdall flash ‑‑RECOVERY twrp‑188.8.131.52‑i9300.img ‑‑no‑reboot
The filename may be different depending on your precise phone model. Type in the actual name of the “twrp” file you downloaded, that ends in “.img”. If there is a connection that becomes loose during this process, you might get a report of 100% upload and success. Don’t worry about this. I’ll write a separate page on what to do should this happen. If all seems well on the phone (the bar is all the way across), then after a few minutes, remove the battery from the phone, put it back in, and start it by going into Recovery Mode.
If all is well, and you’ve successfully installed TWRP, you should see a totally different recovery screen as on the right. at this point, nothing has changed on your phone, if you hit “Reboot” followed by “System”, your phone has not been changed at all, except for this recovery screen. If you get the old recovery screen, then the upload from the computer failed. Mine did several times but I did get there in the end. But what TWRP does, is to give you the power to root your phone, and use a different operating system.
If you see the TWRP screen, go ahead to Part Two.
However, you might see the “Firmware Upgrade Error”. If you do, continue on this page.
This happened to me once or twice, first time I thought it was a disaster and I had bricked the phone. In fact this is caused by an upload that wasn’t quite right, and wasn’t completed. And if you attempt to enter the Recovery screen, or just start the phone normally, you will see the same error. However, you can recover from it. You have to start the phone in Download mode, put in the USB lead, and repeat these two Heimdall commands from earlier.
- heimdell detect
And if the device is detected, then do:
- heimdell print-pit
At the end of that, the device will get thrown back into its standard start screen. You can then try the other two commands to attempt to install TWRP again. You generally “brick” a device by installing something successfully that’s wrong, rather than a failed installation. I went through the loop several times before I got a successful load of TWRP.
Anyway, on to Part Two!