How to install OxygenOS on OnePlus One phone? I have OnePlus One (not rooted) and I'm interested in trying OxygenOS. I tried to follow the instructions in OnePlus forum, but since I didn't have "fastboot and ADB" (&amp; I didn't know what it is), I followed the link to download that. This link said that I'll be downloading a zip file and the steps involved process with that zip file. But what i got was an .dmg file (I'm using Mac), so I don't know if I was doing it right. Any advice? Do I need to root my phone?
Before you start back up all your data, you will lose all your data in this process!

The first problem you have is that the stock recovery tool by cyanogenmod doesn't allow you to put Oxygen OS on there, in other words you need a custom recovery tool.

In order to achieve this follow these steps,


First lets download the fastboot tools here. After going trough a small setup it should generate a folder in your users folder "adb" enter that folder and right click then hit "Open command window here".
Connect your phone to your computer and then hold the power button as well as volume up for approximately 7 to 9 seconds. After that your phone should shows the fastboot screen.
You can check if this works by entering "fastboot devices" into the console. 
Next we are going to unlock the bootloader so we can put a custom recovery on there. Doing this will remove all of your data! To do this enter this command "fastboot oem unlock". The phone should restart now. 
Go into the phones settings and scroll down to "About Phone". In
here scroll down the the "Build number" item and tap it 7 times.
After this developer options should be enabled.
After this leave the "About Phone" menu and go into developer options. In           here uncheck the "Update OnePlus recovery" item.
Now enter fastboot mode again (Step 2).
You have a number of choices by way of recovery tools, my favorite is TWRP, download one and rename the file to recovery.img (this isn't necessary but it makes your life a lot easier later). Then move it into the adb directory.
Its a good idea to remove the old recovery software first, do this by entering the following commands in console you have open from step 2.


  fastboot erase recovery 
  fastboot flash recovery recovery.img 
  fastboot reboot 



If you went with TWRP recovery follow these steps, if not search for a guide on how to flash a image with the recovery you choose.


Download Oxygen OS from the OnePlus website. 

A problem that I see a lot is that people are trying to flash the downloaded   zip file on their device. This doesn't work since you need the zip file in here.  Extract this to your desktop and copy it over to the phones internal storage.
Now you have to enter recovery mode, this is similar to fastboot. Only now you have to press volume down instead of up.
Go back to the main menu and hit "Install". Select the zip file you downloaded and extracted in step 1.
Then go back to the menu and hit "Wipe" and then swipe to the right to do a factory reset. 
After this it asks you if you want to fix root, if you want a rooted phone hit yes, if not hit no.
Your phone now reboots and you should have Oxygen OS!