For those of you having trouble rooting your Sprint Galaxy S4 on latest MF9 firmware, there’s an easy way by using CF Root by XDA user ChainFire.
Step 1. First, you will need to install either CWM or TWRP recovery. Follow a or b below:
a. For installing CWM, follow steps 1 through 6 here.
b. For installing TWRP, follow steps 1 through 9 here.
Step 2. Download the latest CFRoot on your phone (or download on your computer and copy to your phone.)
Step 3. Using CWM or TWRP, find the CFRoot zip file and install it then reboot.
You should have a fully rooted Sprint Galaxy S4 on MF9 firmware.
Credits – ChainFire
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!