The developers behind LineageOS just announced their firmware based on Android 8.1 Oreo. As many of us are still on LineageOS 14.1 (which is based on 7.1 Nougat), I wanted to write out a tutorial to show how to upgrade your current install of LineageOS 14.1 to the brand new LineageOS 15.1.
When we normally update to a newer build of LineageOS (that is the same version of Android), we simply do what is referred to as a dirty flash. This means you download the new build and then just flash it right on top of your current install. This is actually what is happening when you use the built-in updater tool as well. However, this method has never worked well when going from one major version of Android to a newer one.
Back in the day, we would need to do a clean install to update from one major version of a custom ROM to another. This still might need to be the case in this instance too, as I have experienced one flawless update to LineageOS 15.1 (with the OnePlus 3T) and one failed update to LineageOS 15.1 (with the regular OnePlus 3). I will be covering everything that is recommended by the LineageOS developers in the step by step guide below.
Then I will go into detail about what I experienced in the Explanation section at the bottom of the article. This method, if done successfully, shouldn’t cause you to lose any data but you should go ahead and create a Nandroid backup just in case. I will also be talking about how to do a clean flash for those who may want to start with a fresh build of LineageOS.
How to Update LineageOS 14.1 to LineageOS 15.1
- Download the latest nightly version of LineageOS 15.1 to the device
- Download Gapps for LineageOS 14.1 to the device
- Boot the device into Recovery Mode
- Do an Advanced Wipe of the /system partition. . .
- . . .or do an Advanced Wipe of the system/data/cache partitions if you want a clean/fresh install (optional)
- Then install the LineageOS 15.1 ZIP file
- And install the Android 8.1 Gapps afterwards
- Flash any other mods you’re interested in (Magisk, Xposed, etc)
- Then reboot back into Android
So the recommended process for upgrading from LineageOS 14.1 to version 15.1 while keeping your data in tact isn’t very difficult. Once you have downloaded the proper files, you just need to boot into Recovery Mode (which is likely to be TWRP). It’s at this point where I recommend you create a Nandroid backup just in case something goes wrong. If you do have TWRP installed, you’ll want to tap on Wipe, then Advanced Wipe and then select the /system partition so that you can wipe it.
Now go back to the TWRP main menu and tap on Install, browse to where you have the LineageOS 15.1 ZIP file and tap it. Then you can tap the Add More ZIPs button so you can add the Gapps ZIP package to the queue as well. In the video above, I even added Magisk to the queue as well. Once you’re ready to install, swipe the white arrows to the right to begin and then wait for it all to install. Now, when updating my OnePlus 3 I ran into an issue at this part.
I was told that my device wasn’t a OnePlus 3 or OnePlus 3T and it refused to install. If this happens to you, head on over to the OnePlus 3 downloads section on the OnePlus website and grab the latest open beta update listed there. With this ZIP file on the OnePlus 3 device, I was then able to boot into TWRP install this Open Beta, and then follow through with the step by step guide above. Not sure why this happened but I didn’t experience it with the OnePlus 3T.
What I did experience with the OnePlus 3T though was what seemed to be a stuck OnePlus logo splash screen. I waited for at least 15 minutes for the LineageOS boot animation to appear. If something like this happens to you, you’re more than welcome to wait longer to see if something happens. I was worried that the install was borked though so I pressed and held the Power button for a few seconds. This powered the device off and then I turned it back on.
It booted up like normal this time and instantly went to the boot animation screen after the OnePlus splash screen. Even better, this helped complete the upgrade from LineageOS 14.1 to LineageOS 15.1 as shown in the video above.