Sprint subscribers wanting to test out the latest Android 5.0.1 Lollipop can do so unofficially on the HTC One by updating the device with this unofficial CM12 custom ROM. We’ve already documented the same for Verizon and the International models. Now it’s time to let those with the Sprint phone carrier network in the United States enjoy the goodies.

You should know before installing the custom ROM that it’s not made by the official Cyanogen Inc. team or even the real CyanogenMod team. It’s a group of developers out of XDA who have put this one together under the “CM” name. Does that make this any less trustworthy? Not really. It’s still a stable ROM that you can install on your daily phone.

CyanogenMod

Android Lollipop is the step up from KitKat that comes with smart notification with several new features, Android RunTIME (ART) replacing the Dalvik system, Android Beam, tap and Go NFC, updates to the Easter Egg which make it look like Flappy Bird, material design UI and a material design app drawer. The next installment of 5.0.1 comes with bug fixes and performance enhancements over the first build.

  • Read through the list of essentials before starting the guide. Here we remind you with everything you need, the risk involved, some helpful tips and more. Experienced Android users with good memories can skip ahead and start the steps. However, if you aren’t into customizing we recommend taking the time to read over the notes.
  • You must have root access on the HTC One M7 before starting. You cannot install a custom ROM without the system internals opened up away from the factory restrictions.
  • You must have a computer for transferring the files over to the phone. You shouldn’t transfer the files directly to the phone because it’s not as safe.
  • The following is only for the Sprint variant of the first-generation flagship smartphone from HTC which came out last year.
  • Enable the USB Debugging Mode from the Developer Options menu. Find the menu from the Settings.
  • Check there is enough battery life remaining before starting the steps. You must have enough battery so the device doesn’t turn off before the flashing finishes.
  • The ROM is wiped fresh from the data. Unless you make a backup of the OS you lose everything. We do apply the reset during the steps. It’s customary for installing custom ROMs. That means unless you make copies of the data you lose everything including the phone contacts, music, pictures and videos.
  • We recommend taking a Nandroid backup from inside the custom recovery. We are entering the custom recovery mode during the steps so you can take the backup there, or you can do it now just to be safe.
  • You can choose from installing ClockworkMod recovery or Team Win’s TWRP recovery. The guide works for both. However, you must have one installed before coming here. It’s not included in the steps.
  • A Nandroid backup makes a mirror image of the ROM and stores everything you need including phone contacts, apps, games, settings, password, WiFi password, music, pictures, video and even remembers the saved game progress.
  • The Nandroid feature is built-in to your custom recovery, so you don’t need to install it separately. However, if you try out the Nandroid without rebooting by installing the Online Nandroid backup application from Google Play.
  • You don’t need to back up the EFS folder because it’s a HTC device. You are good to go after you store the usual personal data.

How to update the HTC One for Sprint subscribers with CM12 Android 4.4.4 ROM

  1. Start up the computer and login to your user account.
  2. Download the suitable Gapps pack and the CM12 ROM from here.
  3. Use the desktop for the file location.
  4. Connect the phone to the computer with the USB wire.
  5. Transfer both zipped files over to the phones internal SD card.
  6. Disconnect and shut down the phone.
  7. Boot it up in recovery mode.
  8. Take the backup now if you haven’t already.
    – all the data is wiped from this point
  9. CWM users should pick
    – wipedata/factory reset
    – “install zip from SD card,” followed by “choose zip from SD card.”
  10. TWRP recovery pick
    – “wipe”
    -“install”
  11. Now upload the CM12 ROM file.
  12. Confirm the installation.
  13. Do the same for the Gapps pack.
  14. Now go back and select “reboot system now” from the main recovery menu.

The boot up takes longer than usual but it goes back to the normal timing later. If you are experiencing problems the easiest way to overcome anything is by entering recovery mode and performing a factory reset. You can hard reset most devices by using a key combination. You don’t have to successfully boot the phone to enter recovery.