OnePlus One Android Smartphone
OnePlus One Android SmartphoneOnePlus

Prolific mobile software maker, Cyanogen has released the latest CM12.1 series custom ROM to the 2014 flagship smartphone OnePlus One.

This is custom firmware is very different to the one (CM OS 12) Cyanogen had released Android to the device last week. CM 12S is based on Android v5.0.2 Lollipop, whereas the CM12.1 is based on the latest  AOSP (Android Open Source Project) 5.1 Lollipop. It comes with a lot of bug fixes and performance-enhancing tweaks.

Though this 'Nightlies' version is an official CyanogenMod ROM, it is a bit unstable and there are some untested bugs (nothing major of sort) which are yet to be fixed. Cyanogen is working on a more stable M (Milestone) series, until then users can explore the features of new ROM.

Prerequisites (things to remember before installing Custom ROM)

  • This CyanogenMod [official] Android 5.1 Lollipop custom ROM can be installed only on OnePlus One aka Bacon models only; if tried on other devices, it might get bricked [To check your device model: Go to Settings >> About phone >> model number]
  • Though installing custom ROM improves the device's performance and UI experiences, it makes the company warranty void and they will no longer be liable to provide updates in future [users can restore warranty by flashing the device with stock-ROM].
  • Make sure the device is rooted (Bootloader unlocked) before going forward for custom ROM installation.
  • Installation of custom ROM requires clearing of memory in the smartphone, so make sure to back all the data by installing Clockwork Mod (CWM) Recovery/ TWRP in the smartphone.
  • Users make sure they have installed USB drivers on the PC, or else your device (Moto E) will not be recognized by the computer.
  • Make sure your device has more than 80% battery, or else there is chance of smartphone getting temporarily bricked if the installation process is interrupted in the mid-way.

[Disclaimer: This procedure is very technical and should be performed by a person with sound knowledge of rooting (or manual software installation) Android devices. If the step-by-step installation process is not followed properly, there are chances of the smartphone getting bricked or being permanently irreparable. IBTimes India cannot be held responsible for any damage or claims from readers if the procedure does not yield the required results or if the smartphone is bricked. Hence, users are advised to proceed with caution.]

Tutorial: Step-by-step installation procedure of CyanogenMod [Official] Android 5.1 Lollipop CM12.1 custom ROM on OnePlus One (aka Bacon) model:

Step 1: Download CyanogenMod [official] Android 5.1 Lollipop CM12.1 custom ROM (HERE) and Google Apps (HERE/HERE) in to your PC.

[Build version date: 18/04/2015]

Step 2: Connect OnePlus One to PC via USB cord.

[Note: Before plugging the phone to the computer, be sure that you have installed USB driver software, if not, click HERE to download the firmware]

Step 3: Then, place Android 5.1 Lollipop Custom ROM zip file and the Google Apps .zip file into the phone's storage memory. [Note: Users are advised to paste the .zip file in the storage's root folder, not in any other folder.]

[Note: Before users' begin installing the custom software, be sure that the device must have rooted and has installed ClockworkMod Recovery/TWRP tool.]

Step 4: Now, turn off the device and disconnect from the PC.

Step 5: Then perform the regular Recovery Mode sortie by press holding 'Volume (Down)' and 'Power' buttons.

Step 6: After entering the RECOVERY mode, clear the phone memory, by selecting 'wipe data/factory reset'

[Note: use 'Volume' keys to navigate and 'Power' button to select options, while operating under Recovery Mode]

Step 7: Now, clear the cache memory by choosing 'wipe cache partition'

Step 8: Then to go back to ClockworkMod recovery, and select 'advanced' and tap 'wipe dalvik cache' [Note: This step is optional, but many recommend this procedure so that user will not face boot loops or any other errors in the middle of custom ROM installation]

Step 9: Again come back to main recovery screen and then tap 'install zip from SD card'

Step 10: Then tap 'choose zip from sdcard' and go to Android 5.1 Lollipop ROM .zip file in SD card and enter the installation process. Repeat the same procedure to install Google Apps [Note: use 'Volume' keys to navigate and 'Power' button to select options]

Step 11: Once done with the installation process, navigate to '+++++Go Back+++++' and re-start the device by opting 'reboot system now' seen in the recovery menu.

Now, your device (OnePlus One) will take a few minutes to complete the booting process.

Users then head to Settings >> select About phone to confirm the installation of CyanogenMod [Official] Android 5.1 Lollipop CM12.1 custom ROM.

[Credits: Cyanogen.org]