This is a custom firmware update to CyanogenMod 10.1 for the T-Mobile version of the Galaxy S3. Do a Nandroid backup first so you don’t run into trouble. To make the Android simply navigate to back up and restore, then select back up.

This new build is brought out to a host of different devices, some of which we have already covered. It goes without saying that this could be one of the more popular updates that users will get to experience the CM10.1 build on. If you are into custom ROM’s and own one of these mobiles you’ll want a taste of this.

This is for the T-Mobile version only. That is the carrier you bought the phone with. Do not try this on another carrier because it won’t work. It isn’t known if it will cause any damage like it normally would if you were to try to put it on a completely different device, but it’s best not to take that risk.

This build comes with a slight hiccup. Basically, when you make changes to the widget area, it won’t come up straight away. Kind of like a caching issue like your browser would have. If you go out and then unlock it again and then go into the area where the changes are shown, it will work now. So, it does actually make the changes to begin with but you just aren’t able to view them like you normally would. To go one step further, it won’t work until you can view it either. It’s just another one of the little niggle issues we always seem to have with the custom side of things. It’s not a big deal and it’s easily adjusted. It won’t cause any harm or anything like that. Some will find it impossible to deal with, so it’s best we mention it so you can make your mind up first what you want to do from there.

As soon as you open it up after downloading you will see the usual CyanogemMod logo in the blue. The circle area will light up a nice white-blue color and that indicates the loading section. The background everywhere you go will be black. This is the standard way to their ROMs. Personally, I’m a big fan, but some aren’t for this look. There is plenty of videos around YouTube and places like that where you can check out what I mean if that sounds something you might be against before jumping into it. Everything can be reversed, but you might as well just avoid the hassle all together instead of it’s not what you are looking for.


  • The Samsung Galaxy USB drivers.
  • USB debugging mode enabled.

How To Install CM10.1 On Android 4.2.2 Jelly Bean On The T-Mobile Galaxy S3 SGH-T999

1. Go ahead and download the CM10.1 Android 4.2.2 ROM. Many experts also recommend going with the Google Gapps.

2. Connect the mobile to the computer via a USB cord found inside the mobility box.

3. Transfer the files you downloaded to the devices, SD card.

4. Disconnect the device now and then shut it down.

Don’t forget to wipe the cache before you upload the files.

5. Boot it back up in recovery mode. (Home + Volume Up + Power).

To get the file you will need to head to the option on the phone choose from SD card.

This is where the file you downloaded at the start will need loading on the phone.

What you just did with the last two steps you will need to do again exactly the same for the Gapps.