Google has recently launched two new updates for the KitKat OS, and the most recent one is Android 4.4.2. As usual, owners of non-Nexus devices will have to wait a bit longer before they'll be able to enjoy this release, especially if your high-end smartphone is carrier branded.

On the bright side, there are always custom ROMs to rely on if you're looking for means and ways to experience the latest software updates. OmniROM has recently started launching Android 4.4.2 nightly builds for the AT&T HTC One, so if you wish to experience the aforementioned OS, then you certainly can, although, not officially.

This tutorial will guide you through the installation process of the OmniROM custom ROM "Nightly" on the AT&T HTC One (codename "m7att). But, before going any further, you need to understand that nightly builds can contain bugs, as they are not final. The good news is that OmniROM launches nightly builds on a daily basis, so bug fixes are always on their way.

IMPORTANT – READ BEFORE PROCEEDING

  • This guide can be applied only on the AT&T HTC One, codenamed "m7att". Do not attempt to apply this tutorial to any other smartphone or HTC One variant. If you disregard this rule, you may end up with a bricked phone
  • In order to complete this guide, you'll need to have a rooted AT&T HTC One that runs the latest version of CWM or TWRP recovery. If you don't meet these prerequisites, then don't proceed any further
  • During the installation process you will need to factory reset your device. Create backups if necessary
  • Instructions on how to create a NANDROID backup are being provided as well
  • You can use the "Helium" application to backup your app data
  • The "APN Settings Backup & Restore" app can be used to backup your APN Internet settings, and to backup your text messages, you can use the "SMS backup & restore"
  • To backup your contacts, sync them to your Gmail account
  • Before proceeding, enable USB Debugging. To do so, go to "Settings" > "About" > "Software information" > "More" and tap "Build number" until the "developer options" menu is visible. Then, go back to "Settings" > "Developer options" and mark the "USB debugging" check box
  • Make sure that your smartphone has at least 60-70% battery life left. It's crucial that your device does not run out of battery during the installation process
  • Although it's detailed, this guide is an advanced one. If you brick or damage your phone, or if you lose important data, you cannot hold the developers or anyone else responsible
  • Don't skip any steps

What You Need to Download:

IMPORTANT: Regardless if you're going to use the CWM or TWRP recovery, you need to download two zip files first. One contains the OmniROM OS, and the other contains the Google apps. After you download the files, DO NOT unzip them!

  • Download the the OmniROM package by visiting this link. Make sure you sort by "Last modified" and that you download the latest version available
  • The OmniROM package does not include Google apps, so you need to download a separate Gapps zip file. Visit this link to do so.

AT&T HTC One – Install Android 4.4.2 OmniROM Nightly – CWM Recovery Method:

  1. With the needed files downloaded and saved on your computer, connect your HTC One to your PC using the USB cable
  2. Copy both zip files onto your phone's storage
  3. Disconnect your HTC One from your computer, once the files have been transfered
  4. Power off your device. Then, press and hold the "Volume Down" and the "Power" buttons at the same time. This will reboot your device in fastboot mode
  5. In fastboot, select "recovery" in order to gain access to CWM recovery
  6. In CWM, select "backup & restore" and create a NANDROID backup. This file can then be used to restore your current ROM, should the need arise
  7. Select "data wipeout / factory reset" and then from the "Advanced Options" menu, select "wipe cache" and "dalvik cache"
  8. Once you have reset your device, return to the recovery screen and select "Install zip from SD card"
  9. Browse for the Android 4.4.2 OmniROM zip file and flash it
  10. After the OmniROM zip has been flashed, select "Install zip from SD card" again and select the Google apps zip to flash it
  11. Once both zip files have been flashed, press "+++Go Back+++" and then select "Reboot system now"

NOTE: The first time you reboot your device after the flashing process, you will notice that it takes a while for the process to complete. This is normal, so don't press any buttons. However, if the process takes longer than 10 minutes, or if your device is stuck in a boot loop, then you will have to start the guide over. Make sure you don't skip any steps!

NOTE: If you decide that OmniROM is not for you, then you can use the NANDROID backup to return to your previous ROM. Simply reboot in CWM recovery and select "backup & restore"

AT&T HTC One – Install Android 4.4.2 OmniROM Nightly – TWRP Recovery Method:

  1. Connect your HTC One to your PC via USB
  2. Copy the downloaded zip files onto your phone's storage
  3. Once you've copied the files, disconnect your device from your computer
  4. Reboot your handset in fastboot mode. To do so, press and hold the "Volume Down" and "Power" buttons at the same time. Then, boot in Recovery mode.
  5. In the main TWRP screen, you will create a NANDROID backup by selecting "Backup", choosing the type of data that you wish to backup, renaming your file and then swiping the "Swipe to Backup" button
  6. Once you've created the NANDROID backup, return to the recovery menu and select "Wipe". Go to "Advanced" and select "Wipe cache" and "Dalvik cache" as well, and then "Swipe to Wipe"
  7. After the reset has been applied, go back to the recovery menu and select "Install"
  8. Browse for the Android 4.4.2 OmniROM zip file in order to flash it
  9. Once OmniROM is flashed, select "Install" again and flash the Google apps zip file as well
  10. Once the zip files have been installed, return to the recovery screen and "Reboot". NOTE: The first time you reboot your device in normal mode may take a while. If the does not boot up in 10 minutes, or if you're experiencing "boot looping", then something went wrong and you'll need to start over without skipping any steps

NOTE: The NANDROID backup that you have created earlier can help you return to your previous ROM. Simply boot in TWRP recovery and select "Restore"

› See More: AT&T HTC One: Install Android 4.2.2 KitKat OmniROM Nightly (CWM and TWRP Methods)