Install /e/ on a Fairphone FP4 - “FP4”

Tip: Please read through the instructions at least once before actually following them, so as to avoid any problems later.
Warning: Downgrading Smartphones already on Android Q or LineageOS 17.x to Pie or other OS can cause instability or at worst brick some devices
Caution: Flash your device only if you know what you are doing and are OK taking the associated risk. All builds are provided as best effort, without any guarantee. The /e/ project and its project members deny any and all responsibility about the consequences of using /e/ software and or /e/ services.


  • If required take a backup of all important data from your phone on an external storage device before proceeding.
  • Do not take a backup on the same device as some of these actions will format the device and delete the backup.
  • Ensure your phone is charged more than 50%
  • Check that adb and fastboot are enabled on your PC. If not you can find the setup instructions here
  • Download all the files and images mentioned in the download section below before starting the installation
  • Make sure you have a working data cable to connect your device to the PC. There are cables which are only for charging and do not transfer data.

  • Your device requires a code to unlock the bootloader. Get the code here before proceeding with the next steps

  • Enable USB debugging on your device. You can find the instructions here
Caution: Ensure that you flash an image with a security patch level greater than the level of the existing security patch. Failure to do so will prevent you from locking your bootloader.
Tip: On your phone you can check the security patch level here Settings » About Phone » Android Version » Android security patch level. Check the level against the level of the security patch on the /e/OS build as given in the Downloads for the FP4 section below

Downloads for the FP4

Try the /e/ Recovery (limited functionality)

  • /e/OS build : R dev (Security patch: 2022-04-05)

  • /e/OS build : R stable (Security patch: 2022-04-05)

To understand the difference between /e/OS builds check this guide

Warning: Please note some of the above links can lead to external sites

Before install

How to Boot into bootloader mode

This section will be relevant later throughout the guide, when you need to reboot into bootloader mode.

  1. Remove any USB-C cable and turn off your Fairphone 4
    Tip: If you cannot turn your device off, remove the battery for about 5 seconds, then put it back in.
  2. Press and hold the Volume Down button.
  3. Insert a USB-C cable connected to the power (can either be a power outlet or a computer).
  4. Release the Volume Down button as soon you boot into bootloader mode

For more details on how to erase the data on your FP4 refer this guide

Unlocking the bootloader

Tip: The steps given below only need to be run once per device.
Warning: Unlocking the bootloader will erase all data on your device! Before proceeding, ensure the data you would like to retain is backed up to your PC and/or an online drive
  1. Boot the device
  2. Enable and connect Wifi
  3. Enable Developer options
  4. From developer options, enable OEM unlock
    • Get the unlock code from this site and enter it
  5. Reboot on fastboot by running the command in the PC console adb reboot bootloader

    Tip: All the console commands are run on an adb enabled PC and in the adb console.
  6. Ask for unlock with fastboot flashing unlock
  7. Approve with volume + then power
    • The device proceed with a factory reset, and automatically reboots
  8. Reboot again into bootloader
  9. Unlock critical with fastboot flashing unlock_critical
  10. Approve with volume + then power
    • The device proceeds with a factory reset, and automatically reboots

Installing /e/

Installing /e/ using IMG or image file

  1. Boot your FP4 in bootloader mode, and plug it to your computer
  2. On your computer, download the zip file from the link provided above. Unzip the folder and browse into it
  3. Flash /e/ with the following commands:
fastboot flash bluetooth_a bluetooth.img
fastboot flash bluetooth_b bluetooth.img
fastboot flash devcfg_a devcfg.img
fastboot flash devcfg_b devcfg.img
fastboot flash dsp_a dsp.img
fastboot flash dsp_b dsp.img
fastboot flash modem_a modem.img
fastboot flash modem_b modem.img
fastboot flash xbl_a xbl.img
fastboot flash xbl_b xbl.img
fastboot flash tz_a tz.img
fastboot flash tz_b tz.img
fastboot flash hyp_a hyp.img
fastboot flash hyp_b hyp.img
fastboot flash keymaster_a keymaster.img
fastboot flash keymaster_b keymaster.img

fastboot flash abl_a abl.img
fastboot flash abl_b abl.img
fastboot flash boot_a boot.img
fastboot flash boot_b boot.img
fastboot flash recovery_a recovery.img
fastboot flash recovery_b recovery.img
fastboot flash dtbo_a dtbo.img
fastboot flash dtbo_b dtbo.img
fastboot flash vbmeta_system_a vbmeta_system.img
fastboot flash vbmeta_system_b vbmeta_system.img
fastboot flash vbmeta_a vbmeta.img
fastboot flash vbmeta_b vbmeta.img
fastboot flash super super.img

fastboot flash aop_a aop.img
fastboot flash aop_b aop.img
fastboot flash featenabler_a featenabler.img
fastboot flash featenabler_b featenabler.img
fastboot flash imagefv_a imagefv.img
fastboot flash imagefv_b imagefv.img
fastboot flash multiimgoem_a multiimgoem.img
fastboot flash multiimgoem_b multiimgoem.img
fastboot flash qupfw_a qupfw.img
fastboot flash qupfw_b qupfw.img
fastboot flash uefisecapp_a uefisecapp.img
fastboot flash uefisecapp_b uefisecapp.img
fastboot flash xbl_config_a xbl_config.img
fastboot flash xbl_config_b xbl_config.img
fastboot flash core_nhlos_a core_nhlos.img
fastboot flash core_nhlos_b core_nhlos.img

fastboot erase userdata
fastboot erase metadata

fastboot --set-active=a

Locking the Bootloader

Once you have completed the above steps and before rebooting you can and should lock your Bootloader.

  1. Boot your device into bootloader if not already there, and plug it to your computer
  2. Lock critical partitition with the following command
    • fastboot flashing lock_critical
    • Approve with Voume + then power
  3. Reboot again your device into bootloader, and plug it to your computer
  4. Lock the device with the following command
    • fastboot flashing lock
    • Approve with Voume + then power
Success: Congratulations !! Your phone should now be booting into /e/OS !!
Tip: To suggest changes to this install guide documentation, please visit the FP4 specific topic on our community forum. To report issues in the build please refer this guide