OnePlus One Android 5.1.1 Lollipop Update: How to Install Manually Flash Cyanogen OS [YOG4PAS1N0] 12.1[Tutorial]
OnePlus One Android 5.1.1 Lollipop Update: How to Install Manually Flash Cyanogen OS [YOG4PAS1N0] 12.1[Tutorial]Cyanogen Blog (screen-shot)

Early this week, Cyanogen released the official v12.1 OS update for the 2014 flagship smartphone OnePlus One via OTA (Over-The -Air).

However, the new Cyanogen OS 12.1 is yet to reach all parts of the world as the OTA rollout process will happen in phases. If you are impatient, then you can try manually flashing the firmware on the OnePlus One.

The new update is around 645MB in size and brings slew of features including bug-fix to Stagefright security hole. The newer OnePlus One models, which shipped with Android 5.0 Lollipop series, are getting smaller update. It is 304MB in size, reported Android Police.

Salient features of the new Cyanogen OS 12.1 update:

  • Smarter Screen: LiveDisplay intelligently adjusts your screen based on environmental conditions.
  • Calendar Together with Email: Enjoy the latest Boxer powered experience where you can seamlessly share your availability and schedule appointments.
  • Cyanogen Browser: The new Cyanogen browser delivers search results and loads web sites faster and more securely than leading browsers.
  • Redesigned Launcher: App Drawer and Folders have been redesigned for one-handed use.
  • Fresh AudioFX: The user interface has been updated for consistency across all devices.
  • More Playback support: Substantially increased support for codecs for video and audio playback.

Prerequisites (things to remember before installing Custom ROM)

  • This Cyanogen OS 12.1 Android 5.1.1 Lollipop custom has to 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]
  • Make sure the device is rooted (Bootloader unlocked) before going forward for custom ROM installation. [How to unlock Bootloader]
  • 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].
  • 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 (OnePlus One) will not be recognised by the computer.
  • Make sure your device has more than 80% battery, or else there is a chance of the smartphone getting temporarily bricked if the installation process is interrupted midway.

[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. International Business Times, India Edition, 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.]

Downloadable files:

Tutorial: Step-by-step installation procedure of Cyanogen OS 12.1 Android 5.1.1 Lollipop ROM on OnePlus One (aka Bacon) model:

Step 1: After downloading Download Cyanogen OS 12.1 Android 5.1.1 Lollipop ROM on to your PC, connect the 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 2: Place Android 5.1.1 Lollipop Custom ROM zip file into the phone's internal storage memory. [Note: Users are advised to paste the .zip file in the storage 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 TWRP tool.]

Step 4: Turn-off the device and disconnect from the PC.

Step 5: 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 hitting 'Wipe' option

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

Step 7: Come to the main menu and tap 'Install'. S

Step 9: Select the file you download from the PC and initiate installation by tapping 'Swipe to Confirm Flash'

Step 10: Re-start the OnePlus One by selecting "Reboot system"

Your device (OnePlus One) will now take a few minutes to complete the booting process.

Users can then head to 'Settings' >> select 'About phone' to confirm the installation of Cyanogen OS 12.1 Android 5.1.1 Lollipop [YOG4PAS1N0] ROM.

[Credits: Team Android]

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