Since there are no good guides on how to go through the excruciatingly painful process of installing a custom operating system on this phone, I decided to write this guide, which is a step-by-step, easy to grasp guide on how to actually doing, for the few people who still have this phone and want to liberate it. This guide is not perfect and I may have made mistakes in it. If you find a mistake, you can write me an e-mail about it.
Warning! Every retarded guide generated by AI says this, but it's true. there is a real chance that you can brick your phone if you don't know what you're doing. Especially with phones like these. I had a few heart attacks, thinking that I bricked it, I can tell you. Also this lineage OS rom that we'll be installing is based on an outdated version of android (8.1), and it has no official support from lineage.
This guide has also been written primarily for the GNU/Linux operating system because it's easier. Though you will need a machine or a VM with windows installed for the bootloader unlock. The steps here can be also aplied for windows but you will have to look that up yourself.
difficulty: very difficult
Unlocking your bootloader will result in a factory reset of the device. So if you have anything important on your phone, you should back it up.
In order to interact with your phone with android tools on your computer, you will have to enable USB debugging. To do that, you will have to enter developer mode first.
In your android settings, go to system --> about phone, and tap "build number" about 10 times, until a popup message appears saying "you're a developper". A new option should appear in settings --> system.
Then, in the settings, go to system --> developer options and turn on "Android Debugging".
Debian/Ubuntu:
sudo apt-get update && sudo apt-get install android-sdk-platform-tools
Gentoo Linux
sudo emerge -av dev-util/android-tools
If you have a different distro you will have to look up the package name yourself.
Windows
You will have to download the android platform tools for windows. Then extract the .zip into a folder of your choosing, and then open the command line in said folder. You can execute ADB and Fastboot with .\adb.exe [command] or .\fastboot.exe [command]. Optionally you can set a environmental variable to those executables, but you will have to look that up because I don't know how to do that in windows.
These tools essentially allow you to interact with your android phone from the command line on a lower level. It's very useful for other things, like removing bloat from your phone editing system files when rooted etc, but now I'll just use it to install lineage OS on the phone.
This is necessary because Nokia, in their infinite wisdom, has decided that they will disable bootloader unlocking completely with an update. Don't ask me why they would do that, because I have no idea.
Download OST LA and stock firmware.
OST LA is proprietary software that lets you install firmware on Nokia phones without the need for an open bootloader. This software is not free (neither as in price or as in freedom), in fact you can't even buy it. The only way to use it is to have a cracked version.
🐃 GNU+Linux 🐧
The OST LA software is not currently availiable in GNU+Linux, although maybe you can make it work with a VM. 🪟Windows 🪟 First, download this file and <This is the tricky part. Since Nokia doesn't officially support bootloader unlocking in any way, it's up to the community to figure out. Hikari Calyx offers software that can unlock the bootloader, but it costs $5. Personally that is not a tremendous ammount to pay, but I can see how it could be for someone.
You will have to get the following information to complete the payment:
To get FIH build version, plug your (turned on) phone into your computer and execute these commands:
sudo adb reboot bootloader
Now your phone should be rebooted in download mode. To get FIH information, type:
sudo fastboot oem getversions
and you should get output like this:
(bootloader) model=AOP
(bootloader) sub_model=none
(bootloader) software version=AOP-525E-0-00WW-B01
(bootloader) SW model=00WW
(bootloader) build number=B01
(bootloader) hardware version=4.2W
(bootloader) RF band id=G_850_900_1800_1900^W_1_2_4_5_8^L_1_2_3_4_5_7_8_
(bootloader) 12_13_17_20_28_32_38_39_40_41_66
OKAY [ 0.039s]
Finished. Total time: 0.042s
What comes after "software version" is what you need. Write these down somewhere.
Now go to https://hikaricalyx.com/product/nokia-direct-ubl-service/ and request a bootloader unlock service. If the order is successful, that means the hard part is behind you.
Now go to your windows computer (or VM) and download this software, if you havent already. Extract the .zip. Navigate to drivers and click setup.exe. This will install necessary drivers for your phone computer to properly interact with your phone. If you see an error message saying "can't find value of...", that means that the driver is already installed and you can ignore the message.
Now plug your phone into the computer and navigate into the extracted file again, and click HCTSW_Care_UU4.cmd. A terminal window will pop up, asking you to agree to the terms of the service. If you see that, that means the payment was successful.
The program will also ask you whether you want to root your phone or not. Rooting means that you will gain administrative access on your phone, and therefore full control over the device. It is normal to have administrative access on computers, but on phones it's seen as a sin for some reason. If you have no idea what rooting is, just say that you don't want to root your phone. It is not necessary for the system to function, and most people won't get any benefits from it on android.
If you're done unlocking, you can open shampagne and celebrate, because you have successfully finished the hardest part of this process. After your done celebrating, you will have to enter download mode again. If your device is already in download mode, you can skip the following instruction and proceed to step 4. If your phone rebooted into the OS (which will be factory reseted), plug it into your computer and execute this command:
sudo fastboot reboot bootloader
Nothing should immediately happen. The command line will now say "waiting for any device".
Reboot your phone with the command still running and your phone plugged in, and it should reboot into download mode.
First, download these two files: 📀Lineage OS ROM and 📟Firmware files, prefferable to your $HOME/Downloads directory.
Every phone has something called "recovery", you can enter recovery mode when your system breaks for example, and then you can just factory reset from there. We will use recovery to flash a custom operating system on the phone.
Download this .img file, which you will flash onto the phone. Do NOT unzip these files!
Assuming that the file you've downloaded is in $HOME/Downloads, and your phone is in download mode, execute this command:
sudo fastboot flash recovery ~/Downloads/twrp-3.6.2_9-0-PLE.img
If everything went well, TWRP should be installed. Now reboot into TWRP:
sudo fastboot reboot recovery
Now you should be greeted with something like this:
Now go to Wipe and format data.
Now go to Advanced --> ADB Sideload, check Wipe Dalvik Cache and Wipe Cache, then swipe to start sideload.
You will have to sideload both the Lineage OS file and the Firmware file! First sideload the Lineage OS file:
sudo adb sideload $HOME/Downloads/lineage-15.1-UNOFFICIAL-PLE.zip
Once this file is finished, go to the ADB sideload again and sideload the firmware:
sudo adb sideload $HOME/Downloads/firmware-PLE-8.1.zip