Hi i'm new and which android to /e/OS version i need?

/e/OS Devices Fairphone
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Hi!

So, I just bought a fairphone secondhand and want to install /e/OS on it. With all the reads, cautions and warnings i would like to be sure if i think correctly( i can’t see if a recent topic is covering this after reading 20something articles):

My FP5 Googdroid wants to do an update to patch: 5 februar 2026, 20260205

and the /e/OS a15 has a patch: 20260211…. 11 februar 2026?

Is this correct? And i do need to update the fp5 googdroid first to this new patch before flashing the new system? That”s a 2.8gb update. The one installed is 20250623

Another thing; I tried to install adb and fastboot on my fedora42 laptop but can’t make it to start from the command line, i must say i/m not a hero in a terminal and can’t figure out why it doesn’t want to start. I get the message “/adb: No such file or directory” or /adb-devices: No such file or directory, also in none of the underlying folders. It’s very possible that i overlook a small thing

I Don’t want to brick the phone like i read now a couple of times and have these steps not yet ready or confident. Thanks for the help and hope others can be helped by this or other posts, because a community is very handy for troubleshooting, a nifty tool.

(bla/Open source and repairabilty is for me already for a long time a main thing for electronic devices although it’s mainly repearability i can do, open source OS’s are something in a box with different screws and logic. Here i’m at the right spot to get this fixed/bla))

Ciao

Regain your privacy! Adopt /e/OS the deGoogled mobile OS and online services

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The second looks like a build date and not Android Security Patch Level.

From the install page Install /e/OS on a Fairphone FP5 - “FP5” (where it is necessary to open the “Details” section in the red box Cauion) we read:

To check the security patch level on your phone with a locked bootloader, prior to installing /e/OS, open your phone Settings » About Phone » Android Version » Android Security Patch Level .

Then compare it against the level of the security patch on the /e/OS build as visible in the Downloads for FP5 section.

These are the two dates required.

The second date can also be found Releases · e / os / 🚀 Releases · GitLab where today we see

This /e/OS 3.5 version includes all Android security patches available as of February, 2nd 2026.

In general with a Fairphone it is best to avoid the final latest update of the Fairphone OS as /e/OS is likely to lag Fairphone and the whole point of anti-rollback is “Never go back”.

If you plan to relock the bootloader avoid the proposal

Fairphone Android SPL: 5 February 2026
/e/OS   Android SPL:  2 February 2026

is a rollback hazard. :stop_sign:

hmmm … is this the Android SPL?

Supposing you do have an Android SPL of June 2025, while this might look like “a big jump” this is irrelevant for fp5. The /e/OS install script will wipe the phone and bring system and vendor up to date.

The concept is further explored here (answered) Install /e/ on FP5 with newer Security Patches

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This often is an indication that you’re not in the same directory as the application. How did you install adb? (i.e. from a downloaded package, from the Fedora software manager, or with a terminal command?)

You might do a dnf search adb and then a dnf search fastboot to see if those are marked with an i (meaning “installed”) in your system. (I’m not familiar with Fedora, but I believe dnf search ... is the correct command.)

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You might also check out the responses to

adb version

vs

./adb version
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A safe guide to install /e/ on a Fairphone

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Thanks aibd! I see in many threads you need to explaion the date level patch, good work to stay cool.

I’ll check the leads you suggest and:

“Supposing you do have an Android SPL of June 2025, while this might look like “a big jump” this is irrelevant for fp5. The /e/OS install script will wipe the phone and bring system and vendor up to date.”

this will be something to keep in mind, thanks!

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Hi Taurus,

i downloaded the package on the android developer page, first checked the software packages at fedora but could’nt find it. With the adb-install page steps to try to install and run it. But in the terminal i got these messages back. I’ll check the commands you suggest and @aibd . I Did check it while i have to wait an hour before a new answer, with a plain terminal search an android tool came along and sudo dnf5 install, type the program (android-tools.x86_64), enter, did the trick. Program installed and hope to get it to work when the phone is attached

Is the online /e/OS installer doing the adb and fastboot when i flash it that way? Sorry, i need to dive in this before i ask it… Thanks, @piero another newby helped, i’ll check the guide.

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eosinstaller attempts to simply automate the standard method … except where for any local reason it fails. Check a few threads with that hashtag.

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Hi again, to solve this thread with some last questions;

The flashing worked! I now run Murena /e/OS on the fairphone! Thank you for giving information for confidence.

Some confidence is lacking on the locking part. After installing, the fp5 reboots and starts murena. I want to lock critical at least. I had to turn of the phone a couple of times when i typed fastboot flashing lock_critical in a terminal window. After this the bootloader asked me if i want to lock bootloader, because lock critical was already performed by the terminal on the pc quickly.

Last question: “locking critical” parts is good against malicious apps/people? and i don’t need to lock bootloader as it is only a fancy fence what could be hard to come out after locking/ or bricks the phone (where i think i have quite a gap between build patch levels) After reading this locking/unlocking text why would i.. and i have read two threads they had problems unlocking bootloader in /e/OS for an install of a different OS.

Is /e/OS a dead-end OS, a hotel california, where, if you get in and lock it, you never get out??? Or bricking your phone.. Just a smily horror-thought.

Thank you, for the community

PS. Using and reading multiple install documentation (at e.foundation and support.fairphone) and reading a lot of Piero and aibd posts it is pretty easy to install through adb and fastboot install on the pc and the easy step by step tutorials made by the community.

I’m definitely no expert but this magic is working pretty well for me.

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… but you started anyway :slightly_smiling_face: but your were 100% confident of the dates to prevent the anti-rollback hazard?

It is unfortunate that we have lock and lock_critical. Loosely speaking stuck between the two is not to be aimed for.

Without doing anything intrusive please can you take time to read Can't unlock critical partitions.

I cannot tell from your story if you are in a similar position to these two cases.

These commands are non intrusive but please can you show the output of


./fastboot oem device-info

and

fastboot flashing get_unlock_ability

You say:

where i think i have quite a gap between build patch levels

A gap itself is not a problem – simple, just “Never go back”.

Edit @reindier with the actual section you need:

3. Finaly, relock the bootloader (optional)

only how it is mentionned at the bottom of the official instructions in the “Smartphone Selector” for your device → “Official or Community install doc” for your device → “Command line” install page for your device !

only if the android security update in the previously installed OS was

older than the android security update included in the version you want to install

only if the newly installed version is an Official one, not a Community version.

re-enable Developer Options, USB debugging and allow OEM unlocking

with the device in bootloader mode,

  • Open a terminal from the “/platform-tools” location
  • and check bootloader status by running :
./fastboot oem device-info


./fastboot flashing get_unlock_ability

if the return is 1

→ you will be able to relock

if the return is 0

→ you will not be able to relock now, it is advised to

  • to relock critical partitions, copy / paste this command :
./fastboot flashing lock_critical
  • Approve with volume + then power

the device may reboot into system,

re-enable Developer Options, USB debugging and allow OEM unlocking if needed,

and re-run

fastboot flashing get_unlock_ability

if the return is 1
→ you will be able to relock

if the return is 0
→ you will not be able to relock now, it is advised to

  • to relock the bootloader, copy / paste this command :
./fastboot flashing lock
  • Approve with volume + then power

the device must reboot, if not, copy / paste this command

./fastboot reboot

boot to the system,

and disable “allow OEM unlocking”, “USB debugging”, and “Developer Options”

the bootloader is now relocked.

.

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It is unfortunate that we have lock and lock_critical. Loosely speaking stuck between the two is not to be aimed for.

Exactly! This has cost me 60 € and two weeks without a phone.

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Here is what returned from the fastboot oem device-info

./platform-tools/fastboot oem device-info
< waiting for any device >
(bootloader) Verity mode: true
(bootloader) Device unlocked: true
(bootloader) Device critical unlocked: true
(bootloader) Charger screen enabled: true
OKAY [  0.001s]
Finished. Total time: 0.001s

From the fastboot flashing get_unlock_ability

fastboot flashing get_unlock_ability
(bootloader) get_unlock_ability: 1
OKAY [  0.001s]
Finished. Total time: 0.001s

So the FP5 is unlocked in all stages… and preferable lock it anyway. My spl is 5 june 2025 and have /e/OS latest IMG-e-3.5-a15-20260211580868-official-FP5 just installed

bootloader version is C.059.20250908, but has nothing to do with it i believe

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I enabled developer settings in the /e/OS settings again and USB debugging enabled, then followed this FP5 lock/relock tutorial for locking the FP5 again.

Now i redid the check with oem device and it returned this

 ./platform-tools/fastboot oem device-info
< waiting for any device >
(bootloader) Verity mode: true
(bootloader) Device unlocked: false
(bootloader) Device critical unlocked: false
(bootloader) Charger screen enabled: true
OKAY [  0.001s]
Finished. Total time: 0.001s

Other command returned

fastboot flashing get_unlock_ability
(bootloader) get_unlock_ability: 1
OKAY [  0.000s]
Finished. Total time: 0.001s

Is the last get_unlock_ability to see if it went well and i can unlock it again afterwards?

On the bootloader mode the device state is -locked and /e/OS Murena is booting normally and wiped my little input i gave him…

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i think if you go to developer options and disallow “OEM unlocking”, then fastboot flashing get_unlock_ability will return (bootloader) get_unlock_ability: 0

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Yes, after engaging developer abilities (again, same as in googdroid) and lock oem unlocking it replies with”0”, after restarting in bootloader.

Now developer abilities are enabled in /e/OS and can be undone by the switch

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