OnePlus One: Flash OxygenOS, Cyanogen OS 12S, CM 12.1

OnePlus One is the geek’s phone. It’s kind of the new Nexus. So it’s a shame that upgrading this phone to Lollipop is not smooth as candy.

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If you’re in India, you’re not even sure if you’re going to get Cyanogen OS 12S OTA update. The rollout is slow and users get frustrated when checking for updates returns nothing. And OxygenOS might be the biggest blunder of it all. To install the official Lollipop upgrade from OnePlus, you need to unlock the Bootloader, manually flash a custom recovery and then flash a zip file. You might as well just root the phone while you’re at it.

It’s a good thing OPO has been established as a geek’s phone. Can you imagine a Samsung or HTC phone coming out with such an abysmal upgrade system?

But you want the Lollipop. You need it. So you’re going to spend the couple of hours getting it. And be honest, you like this part a little bit. It gives you an odd sense of authority. It makes you feel good about yourself.

Ok, so below you’ll find instructions and links to files for flashing OxygenOS (Android 5.0), CM 12S (Android 5.0) and CM 12.1 (Android 5.1). This isn’t going to be short, so grab a cup of coffee.

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Choices, choices, choices.

1. Manually Update To OxygenOS

OxygenOS is the official Lollipop ROM from OnePlus. But because it’s not from Cyanogen, there’s no OTA update. In fact, there’s no easy way to flash this thing.

While you don’t need root access, you do need a custom recovery to flash OxygenOS (because currently you’re running CM recovery and that’s obviously not going to play well with OnePlus). And you need to unlock the Bootloader. Which means all your data is going to be deleted.

All about custom ROMs: Check out the three top custom roms, what makes CM 11 awesome, and the tools that make a frequent custom ROM flasher’s life easier.

I have covered how to unlock OPO’s Bootloader and install custom recovery in the OPO rooting guide. The steps here are going to be the same. So click here and follow step 1 to 4 and then come back.

Step 1: Download the zip from here and extract it. You’ll find two files. The zip file with the flashable at the end is the one you want.

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Step 2: Copy the file to the root folder in OnePlus One.

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Step 3: Now, we’re going to boot into TWRP recovery by holding down the Power + Volume Down keys. I’m assuming that by now you have unlocked the Bootloader and installed TWRP custom recovery.

Step 4: Before we begin, let’s take a backup of the current ROM. Tap Backup and then swipe to confirm.

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Step 5: Now, let’s make sure CM is gone before we install OxygenOS. Tap Wipe and then swipe to confirm. This will do a factory reset.

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Step 6: Go back and tap Install and tap on the flashable zip OnePlus file and swipe to confirm flash. After it’s done, tap Reboot system.

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Your OnePlus One will now boot up with a fresh install of OxygenOS Lollipop 5.0.

2. Manually Update To Cyanogen OS 12S (No Root Needed)

If you’re tired of waiting for the Cyanogen OS 12S OTA to show up or if you’re in a country where you’re not even sure you’re going to get the OTA (**cough** India **cough**), why don’t you just manually update to CM 12S. Hey, it’s a lot easier than flashing OxygenOS, I’ll tell you that.

You don’t need to unlock the Bootloader or flash custom recovery. You won’t even loose any of your data.

Step 1: To get started, first, download the CM12S flashable zip from here and transfer it to your phone.

Step 2: Just to be safe, do take a backup of all your important data before beginning the update.

Step 3: Go to About phone and tap the build number seven times. Then go to Developer options and from the top, enable Advanced reboot.

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Step 4: Press and hold the power button, tap Reboot and choose Reboot recovery. You’ll now be rebooted into CM recovery.

Step 5: From here tap Apply update -> Choose from internal storage -> 0/ and select the CM 12S zip file. This will begin the flashing process. It can take several minutes.

Step 6: After that you’ll come back to the recovery menu. Here, select Wipe cache partition and then reboot the system.

You’re now running CM 12S.

3. Manually Update To CM 12.1 (Root Needed)

If you want to skip the whole official process and just want the latest and greatest from CyanogenMod (which is different from Cyanogen OS), this is the best way. In fact, this is the method I went with.

For this, you’ll need to have an unlocked Bootloader, TWRP custom recovery and you’ll need root access. You can follow the guide on how to do that here.

Once you’ve done all that, we can flash CM 12.1 custom ROM. Remember, as you’re flashing a whole different ROM, your data will be deleted.

Step 1: Download the latest CM 12.1 Nightly from here and get the Gapps. Transfer both files to your phone.

Step 2: Press Power + Volume Up to boot into TWRP recovery. Here, first tap Backup and swipe to confirm to take a backup of your current ROM.

Step 3:: Now, we need to wipe the current CM ROM. Tap Wipe -> Advanced wipe and select Dalvic Cache, System, Data and Cache. Swipe to confirm.

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Step 4:: Go Back. From the main screen tap Install and select the CM 12.1 zip file.

Step 5: Now again go back and clear the Cache and Dalvic Cache.

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Step 6: Go back to Install and this time flash the Gapps zip file. Once that’s done just reboot the system.

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How’s Your OnePlus One Doing?

Do you like your OnePlus One? Do you hate it? Is it just OK? Share with us in the comments below.

Last updated on 03 February, 2022

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