AT&T Galaxy S4 updated to version I337UCUFNI1, root is recoverable

Update: New update with Android 4.4.4 (NJ4) has been rolled out, it’s still root-able.

About six months ago the AT&T Samsung Galaxy S4 has been updated to Android 4.4.2 with software version I337UCUF(NC1) KitKat, since then the phone is not getting any update again, until we get the update notification today. However, it seems that this update is not as we expected, there’s no OS upgrades, just performance improvements and bug fixes. The new software version is I337UCUFNI1, it’s not a major update, since the file size is only 121MB-977MB, but depending on your current Android version. Although it is not a big update, but root access will be lost after you download and apply the NI1 update.


The T-Mobile Galaxy S4 users seems to be lucky enough as their phone have been updated to Android 4.4.4. However, the NI1 version also brings improvements that exist in the latest version of KitKat like the Google security patch, which will make you better protected when using this phone. In addition, it delivers an updated version of Google apps as well as connectivity improvements related to receiving calls and texting.

For rooted users, there is no need to stress, simply because we can take back superuser access with towelroot. Since this app released by geohot, rooting effort became a lot more easier. The procedure to restore root on I337UCUFNI1 software for AT&T Galaxy S4 are similar to other Samsung phones, which utilize towelroot-compatible kernel. We should give thanks to an xda user – muniz_ri, who brave enough to take the risk trying this method on his phone.

att galaxy s4 ni1 root

Image: Samsung / AT&T

Update AT&T Galaxy S4 to I337UCUFNI1 and regain root

For those who still want to get superuser access again after running the official NI1 update from Samsung, then you need to prepare the following files:

  • Stock kernel from I337UCUF(NC1) firmware.
  • A life saver utility – Towelroot app by geohot.
  • Another stock kernel extracted from I337UCUF(NI1) firmware.
  • Odin flash utility for Windows computer.

For a complete guide and the troubleshooting you can go directly to muniz_ri’s thread on xda. If you have no idea about what you will do, here we summarize the steps for you:

  1. Initiate an OTA update to NI1 version.
  2. Put your phone into download mode.
  3. Run Odin on your PC, then flashes the NC1 kernel (PDA/AP).
  4. Instal towelroot, then obtain root.
  5. Flashback the NI1 kernel with Odin.
  6. Profit.


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3 Responses

  1. bjay
    September 19, 2014 at 12:35 PMReply

    I am able to root my S4 SGH-i337 with this method and it worked flawlessly.

  2. Josh
    September 29, 2014 at 4:31 PMReply

    It says I’m rooted once again. Can I install a custom rom. Or do I need a rom with the NI1 firmware

  3. gerry
    October 2, 2014 at 11:13 AMReply

    How to initiate an OTA update to NI1 version? My SGH-I337 is already updated to 4.4.2 version with baseband version I337UCUFNI1. Pls, help. TY.

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