Are you using the OnePlus One smartphone and looking to run and unofficial Android 5.0.2 Lollipop-based custom ROM? If so you can do that now with the official OxygenOS ROM. I’ll show you how to download and install the new ROM after the jump.

REQUIREMENTS

• You can only install the OxyegenOs custom ROM on the OnePlus One phone and no other.
• You must have root access on your phone before you can install the OxygenOS ROM. You can root yours via a toolkit here.

BEFORE WE BEGIN 

• You must setup ADB and fastboot on your Windows PC by using our guide here. You don’t need to do it again if you already have ADB and fastboot setup, regardless of the device you were using it for before.
• You’ll also want to install the OnePlus One USB drivers on your computer if yours aren’t up to date. Restart the computer after installing the new drivers for them to work. Having problems getting it to work? This is probably why.
• Download the OxygenOS custom ROM from here over to the root of your phone.
• Download the TWRP recovery (custom recovery) from here.

HOW TO DOWNLOAD AND INSTALL THE OXYGENOS CUSTOM ROM IN ONEPLUS ONE SMARTPHONES

1. Transfer the TWRP recovery file to the fastboot folder you created while setting up ADB and fastboot from above (in Android SDK).
2. Enable the unknown sources option on your phone by navigating to Settings > Security.
3. Boot to fastboot mode: hold down the Power + Volume Up keys.
4. Wait until you see the fastboot logo and then connect your phone to the computer with the USb cable.
5. Run the Command Prompt on the Windows computer and navigate to the fastboot folder.
6. Type the following commands:
7. fastboot flash recovery <recovery.img>
   fastboot reboot
8. You now have the custom TWRP recovery installed.
9. Enter recovery mode on the phone by holding the Power + Volume Down keys.
10. Important: take a Nandroid backup now because you are going to wipe the current ROM clean. That means all your precious baby/husband/wife/local hobo photos lost unless you can restore them.
11. Navigate over to the “install’ option from inside recovery and upload the OxygenOS file you downloaded earlier.
12. Reboot after the ROM is flashed.
13. Now you have the OxygenOS ROM running on your OnePlus One device.