Cosmo Communicator (clamshell)
Comes with android
Support website not yet updated with Linux flashing guide
Question: phone functionality when running Linux?
Question: since android system partition is RO, will Linux be RW?

Cosmo Astro - a slider from Cosmo

Fxtec Pro1 (slider)
Comes with android
Can run lineageOS (Android-based rom)
Can run Jolla’s sailfish OS (closed-source components)
Future ports may become available

Purism Librem5 (slate)
Runs PureOS
Not quite a daily driver yet?

PinePhone (slate)
Currently ships without OS
Runs any open mobile Linux platform
In active development





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These are the notes I’m taking for myself as I shop for a new device. Thought they might benefit someone else here.
It’s my effort to capture and keep track of the state of things.
Trying to focus on “daily-driver” FOSS options without any personal bias.

FOSS stands for free and open source software.

Even Android is mostly FOSS, and I think none of the devices you mention run only FOSS (some firmware blobs & closed device drivers are ususally required)...

Are you really looking for free & open hardware? Completely free and open, or just “mostly”?
I know of no device that would fulfil that; maybe the OpenMoko in its day.

The only attempt at making a completely FOSS smartphone OS (software, not hardware) is Replicant.
Are you going to add the devices it supports to your list? Probably not.

Depending on what you really mean I can think of some articles to add to your list, or some to remove...

Please be more specific on what you really want here. It seems to me that the term FOSS does not apply.

I would interpret 'FOSS phone' as described in the OP as 'Mainline Linux compatible phone' or 'Open source OS compatible phone'... which would make sense considering the listed phones.

Sorry but no.
What you wrote is just as vague.
Tell me:
What is "mainline Linux"? The current kernel?
When a phone is "mainline Linux compatible", what does that entail? That the kernel can be made to boot? That the kernel can access all the hardware? That there's a full graphical UI that can also access all the hardware? - These three steps are increasingly strict and afaik currently nothing goes all the way to the third step. Maemo Leste is working on it but still pretty far away.
Would you add all the hardware that can currently boot Maemo Leste to OP's list?

And what is an "Open source OS compatible phone"?
A phone that can run an open source OS? AOSP is open source. Does that mean all Android devices then?
Are we allowed to add firmware blobs? LineageOS does exactly that. Again, that would add a huge pile of devices nobody's interested in listing here.

I could go on for hours.

This is a pet peeve of mine.

What people usually mean when they write something like "FOSS phone" is some sort of "independent" phone, made in small batches, crowdfunded, often making exactly those sort of vague promises about Linux & FOSS & "a wonderful community".
Upon closer inspection they are in no way "better" or "more FOSS" than your average Android device, or Intel laptop, only: this sort of credulity in buzzwords makes it possible for some companies to draw profit from making statements that are just shy of false claims.
It also produces disappointment in those that "believed" in those big words.

Don't get me wrong, I am not against these attempts at all, and I am not against OP making a list.
I just don't like if someone uses a strictly defined term for something so vague.

There's another way to define this niche: compatibility with an unpopular mindset and/or technical requirement such as "The phone is a computer and it should act like a computer" (opposed to internet connected appliance).

N.B: Plasma Mobile is an interface, not a OS. Also LuneOS is open enough and linuxy enough to be considered alongside the other options.

I like @wx9's define for niche, and I agree that the term FOSS in here may not be accurate and might not even be OP's thoughts. (Thank you for the elaboration, @nonsuch)

In my personal opinion, it's the device/service that does not follow the trend and mainstream, or follow what mega company / organisation / or even gov, want you to be.

In my guess, the intention of OP could be:

Hardware wise:
- Has certain degree of freedom of components control / driver (Purism, PinePhone)
- Has certain characters that against the trend of mainstream modern phones (Fxtec Pro1)
- Has freedom to choose which OS to run, and not locked to a certain OS

Software wise:
- Has true multitasking like desktop, unlike Android and iOS
- Has a certain level of openness, user can easily tweak and customise and play/kill the OS without breaking many rules
- Has a slightly better transparency of what the OS does or if it collects info of where you are what you searched or even what you say
- Not having millions of services and free games that occupy your time and make mind ******ed.......

Unfortunately nothing is perfect in this world, even our beloved N900 / N950 is not completely FOSS. But the most important is there are people trying and there are users to support the effort swim against the stream.

Mainline is what you get from https://github.com/torvalds/linux
Not necessary the HEAD but some defined branch.

Yes

If you can get an UI on it, what is preventing you to access all hardware?

No blobs, that's my definition.
That is the largest problem and it rules out a lot of SoC's. Basically the way to go would be what Neo900 tried to do, having a separate chipset for handling the communications, not combined with the host CPU.
Think of it like a computer that has a 3G/4G USB stick hanging off the side. All the blobby bits are inside the dongle, and the computer may run with only open components.

Please don't

I can see that.

You do realise that you can do this for virtually any subject, right? And to be clear, with 'this' I mean go on endlessly asking for very specific definitions instead of attempting to understand what is meant by reading the context.
Juiceme answered most questions as I would.

Purism Librem 5 and Pine64 Pinephone both do this (see also this article), so I would say those two are good start for 'FOSS phones'. Although display and wifi/bluetooth drivers also seem to be a concern, often.

However, if you want to take it that far, there's not a single device out there that's runs on 100% open source software. Nor does there need to be in my opinion, companies have to right to execute their specific solutions (which they presumably worked hard for) in a proprietary fashion.

Hence my earlier defined understanding of what 'FOSS' phone means for me; runs 'mainline linux compatible', meaning it can run a recent version of the kernel (which is FOSS), drive the phone's hardware (which can partly FOSS), and run a GUI/DE (which can perfectly be 100% FOSS).

FOSS, not FOSS, linux or not - well, yes linux!
But
I personally don't want my data to be used without my acknowledgement. It is private, it is personal, it is my life, my friends, my thoughts, my tastes, my pictures.

Brands, apps, games, leave me alone until I call you!

But if you come home, you, reader, user, I would share, because I met you, because you are a human.

This is my definition of a fair machine. I want to be free, not the machine.

Cheers

Wow, I didn't expect to start a conversation with this post, but I appreciate the response.

@nonsuch is absolutely correct, I was using the term FOSS in a very hand-wavey (and wrong) sort of way. I can respect his pet peeves, as I have mine.

I feel like I represent the "average" linux user. I use linux both personally and professionally as a tool. Part of my job involves software development but I am not a software developer so sometimes I get mixed up and say desktop environment when I meant window manager.

@wx9 had it right - the phone is a computer and it should act like one. On android you can modify system files, but the phone re-loads the system ROM on reboot so the change isn't persistent. For that you have to re-flash. That's not how a computer works.

Open-source mobile hardware is extremely rare, and I don't mind if my wifi driver has to be a binary blob if it gets me the experience I am after. It's a compromise. So I guess that's not "FOSS".

@chenliangchen mentioned "freedom to choose which OS to run". I'm not sure that's really so important. I would be happy with one option for the underlying linux system if I could then choose which interface to put on top of it. My understanding is that Maemo did not - and Sailfish does not - have that capability due to parts of the system being closed-source. This may have been where my use of the term "FOSS" came from.

I don't need a variety of different operating systems - just one that's open enough for me to tailor to my needs.

I'll replace the term "FOSS" with linux in the original post and welcome any additions or corrections to the list.

And before someone says "such-and-such device on your list doesn't meet the requirements you just laid out".... yes I am keenly aware of that. I desperately hope that some day one of them will.