Last week, we announced that the OnePlus One finally begun delivering its Android Lollipop-based Cyanogen OS 12 OTA (over the air) in select regions. Now, another OS announcement for the OnePlus is creating some buzz as well.

CyanogenMod has recently unveiled its BlissPop ROM custom update. Unlike the  Android Lollipop based Cyanogen OS 12, the BlissPop ROM custom update delivers the latest Android 5.1 upgrades and is completely based on the original CyanogenMod source code.

For European OnePlus One owners that wish to update their software to Android 5.1 status, the latest BlissPop ROM delivers all the latest enhancements and bug-fixes found in 5.1 Lollipop.

The latest unofficial BlissPop ROM update was found by the Android Soul. Without further ado, here is the step-by-step guide to the BlissPop ROM manual installation.

Prerequisites

  • Verify device model number via Settings > About Phone. Guide is intended for European variant of OnePlus One only
  • Ensure the phone has at least 80% battery charge before installing the ROM to avoid battery drain.
  • Back up data and settings.
  • Verify correct USB drivers for the OnePlus are installed on the computer (download OnePlus One USB drivers).
  • Enable USB Debugging mode: Settings > Developer Options (Android 4.0 or newer) or Settings > Applications > Development (Android 2.3 or earlier).
  • Ensure that the device is rooted with CWM recovery installed and its bootloader is unlocked.

Download

Android 5.1 Lollipop BlissPop ROM for OnePlus One

Google Apps             

Install Android 5.1 Lollipop BlissPop ROM for OnePlus One

1.      Download Android 5.1 BlissPop custom ROM for OnePlus One on the computer.

2.      Connect and mount the phone's USB mass storage on computer with USB cable.

3.      Copy downloaded BlissPop ROM zip file to the root folder on the phone's SD card.

4.      Power off the phone and disconnect its USB cable from computer.

5.      Boot the device into Recovery Mode: press and hold Volume Down and Power buttons together.

6.      Once the phone enters CWM Recovery, perform a full data wipe via Wipe Data/Factory Reset. Use Volume keys to navigate between options and Power button to select an option in the Recovery Mode.

7.      Perform Wipe Cache Partition. Wait until the process completes.

8.      Perform Wipe Dalvik Cache: Go to 'advanced' option and then click Wipe Dalvik Cache. This prevents boot loop issues or any boot ROM related errors during firmware installation.

9.      Return to main recovery menu and select Install Zip from SD card.

10. Click Choose Zip from SD card and select the BlissPop ROM zip file. Confirm the ROM installation to begin process. Note: Repeat Step 9 and Step 10 to install Google Apps (Gapps) as well.

11. Once ROM and Gapps installation is completed, select Reboot System Now in the Recovery menu.

The first reboot following the installation may take about five minutes to complete. Your OnePlus One is now running the latest Android 5.1 Lollipop via BlissPop custom ROM.