Headphone jack:

Get a USBC adapter

Batteries:

Not easy to change, check out ifixit

Debian <> Pixel data transfer:

USB, or Wireless across any protocol you can imagine.

My experience with GOS:

Contactless payments and some QR code payment methods from banking apps in my country refuse to work with GOS.

Otherwise, I love it. Very easy to install and use. Recommended.

I’ve been using grapheneOS on and off since I got my pixel 8A about a year ago. I keep going back to stock android because Graphene has so many quirks and shit that kind of works, but not quite well enough. That coupled with all the completely breaking issues with banking apps and other apps (we have a 2FA app for official online stuff, but it just doesn’t work in graphene) makes me give up every time I try.

I’ve been using GrapheneOS for at least 5 years now (still remember the days when their sandboxed Play Store would need a force stop after every app install 💀) and I’m a much heavier user than you (social media, YouTube/podcasts, etc.). At this point I would not use anything else.

You won’t have issues with app compatibility except for certain banking apps and Google Pay, if you choose to install the sandboxed Google Services. If not, you’ll have issues with some apps not sending you push notifications (for example, Discord and Proton Mail) and other apps not working entirely (like Snapchat). Still, the last time I tried going fully de-Googled I remember most apps still working well enough even without Google services. From your post it sounds like you could easily live without it.

Sadly the newer phones have no headphone jack, and you definitely should not go for older ones that don’t recieve security updates. And the Pixels have never had removable batteries (you can check out iFixit for more info on repairability). Any Bluetooth headphones will work. They do have a 3.5mm jack to USB-C adapter but I it never worked for me.

Data transfer between Linux and Android has always been dead simple regardless of the OSes involved. Just plug the phone in and tap a couple of things, the phone’s filesystem will show up on the PC like any USB drive.

I use GrapheneOS on a Pixel 8a. About 6 months in. The recent “a” series models are a pretty good deal as they come with 7 years of updates from initial release.

I love GrapheneOS. Pretty much just works. Many Apps do not even have to have google play installed. There are some apps that may not run. Typically those that require an original authentic device. My banking app did not run originally but now it does. Not sure but I think I had issues with the UPS app for some reason. I switched to the web for that.

Ive used grapheneOS for a few years, and I also used calyxOS. If you’re looking for maximum security, go with graphene, if you’re more of a beginner and need easier usability, calyxOS. Both are great but graphene does require more tinkering IMO if you’re worried about that sort of stuff

My main OS is debian. How easy is to transfer data from GrapheneOS to debian and the other way round?

KDE Connect works great for me

Is there a pixel device with a jack port?

Not that still has security updates? Something to note is that gOS stops supporting pixels after security updates stop, so factor that into your decision. I use a qudelix-5K bluetooth adapter which has excellent sound (and balanced and onboard equalizer, flawless 96Khz/32bit LDAC from my pixel 7, also doubles as a USB DAC), it’s expensive but after 2 years I still think it’s one of my best recent tech purchases.

Are batteries inside pixel devices glued to the frame or can they be easy to change?

I had to replace mine and chose to use an iFixit kit, first foray into glued repair and while fraught it went fine. Removal wasn’t that bad, there’s a plastic strip under the battery to help get the bastard out.

My main OS is debian. How easy is to transfer data from GrapheneOS to debian and the other way round?

Syncthing.

2 odd years in and it works great for a similar use case to yours (music [PowerAmp, paid], books [Moon Reader, paid], maps [still on Organic], notes [joplin], camera [google], web - ironfox, mail [proton]). Network deny permission is a godsend, most things on Google Play Store can be installed (even paid will usually work, but some use more aggressive checking) and then you can uninstall the Play store and services and deny network to anything that might call home and everything just works, including full google camera (see my history for details). A bit of onboarding hassle finding replacements, but well worth it, updates happen a lot more often than you are used to, but it’s a good pain. I also have a second user with full Google play and a few other apps, but I can’t remember when I last spun it up, good training wheels for adaption.

As long as your headphones are Bluetooth, they will continue to work fine.

I haven’t run Graphene OS since I broke my Pixel 3a and went with a different device. But when I did run it, it was perfectly fine.

With that said, I ran lineage before I ran graphene and I ran lineage after I moved away from graphene.

You should probably also consider CalyxOS, which supports most Pixel phones and, for me at least, seems to work with banking apps using microG while removing all of the pre installed Google bloat and providing a firewall.

That said, I haven’t tried GrapheneOS. From what I hear you can lock it down even more and there are more features.

Head phone jack. My 8a sadly has none. Not sure any recent Pixels do. I use combination of some HP OTC hearing aids and a Senhouser headset, both blue tooth.

Files transfer. I mosly use Nextcloud or just plugin my phone to my computer directly with USB. I have used syncthing and ssh too. Debian should work but I have more experince with Ubuntu and the USB method works fine there.

I’ve ran LineageOS until two years ago from when it was CyanogenMod on my S3. Been a Debian user a bit longer. ;-)

What it’s got over LineageOS is it sandbox stuff out the box, so you can compromise with Google Maps and things like Bank apps run.

For work, I need a satnav with traffic in it’s route planning. No matter how good Organic Map’s maps are. Also for work, I need a Bank app. I’m not really happy with GrapheneOS, but I don’t have a choice. It’s my least worse option. Unless I keep a GrapheneOS phone for work and maybe try a Mobian phone for home… When it looks day drivable…

Edit: oh and transferring files, Nextcloud or scp in Termux.