Since, everyone seems to be asking me if there’s root method for AT&T Galaxy S4 MF3 (and I don’t think I can respond back anymore to the same question over and over again), you can root it using Verizon ME7 root method!
For those of you already rooted, I suggest you do not update to the latest MF3 firmware as you will be able to root it but you won’t be able to install custom ROMs as there’s no way to install custom recovery yet!
What is a Custom ROM?
A custom ROM is a custom, modified operating system that you can install on your Android device. Basically it's like installing Windows OS on a Macbook. By installing a custom ROM, you can bypass stock factory settings like locked hotspot tether, install new Android versions early, or even convert your phone into another OS.
With a custom ROM, you can really maximize the capabilities of your smartphone by adding custom features that have been developed by open source developers.
How to Install Custom ROMs
First, you will need to root your device, if it is not rooted yet, follow our root tutorial and root your phone.
Once rooted, you should have TWRP installed on your phone. Installation of a custom ROM is easy if you learn the basic of it. If you don't know how to install custom ROMs using TWRP recovery, see our tutorial on How to Install Custom ROM using TWRP!