audio mastering engineer at Total Sonic Media - https://totalsonic.net/
Unfortunately Samsung is making it more difficult to impossible to unlock the bootloaders of their recent devices, but you can reflash some of their older models at least to ROM’s like crDroid - https://crdroid.net/
The best general resource for instructions on how to unlock your phone’s bootloader and flash alternate AOSP ROM’s or non-Android OS’s is https://xdaforums.com/
Please note that not all carriers and oem’s allow you to unlock the bootloader though, so choose your device carefully for this.
You will also most likely need a PC (desktop or laptop) with adb & fastboot on it. These are apps used in the terminal, but you only need to copy and paste a few commands into them to use it.
If you have a Google Pixel then best option is Graphene - https://grapheneos.org/
For other devices you can use a “degoogled” Android ROM and get apps from the open source F-Droid app store - https://f-droid.org/
Some choices for this are:
Lineage - https://lineageos.org/
crDroid - https://crdroid.net/
/e/os - https://e.foundation/e-os/
Iode - https://iode.tech/iodeos/
OR use a a true alternative mobile OS. Options for this are:
Ubuntu Touch - https://www.ubuntu-touch.io/
Sailfish OS - https://sailfishos.org/
Mobian - https://mobian-project.org/
Postmarket OS - https://postmarketos.org/
Plasma Mobile - https://plasma-mobile.org/
Droidian - https://droidian.org/
You can also purchase devices with alternative OS’s already preinstalled from:
Volla - https://volla.online/en/devices/
Jolla - https://jolla.com/
Fairphone - https://fairphone.com/
Murena - https://murena.com/
Furilabs - https://furilabs.com/
Brax - https://www.braxtech.net/
“Don’t be an idiot” - yet the big idiocy I see over & over on the Fediverse are Graphene evangelists that want to knee jerk condemn the multitudes of other mobile libre projects that are doing some good things, with its supposed (and disputable) “perfect”.
Graphene is indeed the current best solution towards security hardening for mobile devices, and I would certainly recommend it as first choice especially for anyone working in truly sensitive areas (e.g. journalism, political activism, closed source design, utility maintenance, etc.), or for whom anyone for which security is their primary concern.
However - at this point Graphene is 100% dependent on Google for continuance - both to a large extent the coding of its AOSP base, for the timely security updates Graphene prides itself on, AND in ALL of the hardware it currently supports. As such, given Google’s direction, with the next gen Pixel phones likely not to be easily unlockable, and with security updates possibly only provided in a timely way to an insiders list of oem’s, until Graphene issues their own devices, or expands beyond only Pixel support, it faces a potential expiry date (similar to what has happened for CalyxOS).
Meanwhile there are TONS of use cases of people with devices from all kinds of oem’s, that simply want an experience on these that offers better privacy and more digital sovereignty relative to what Google & Apple offer. As such one can achieve a close to an ad free & data mining free, with much less overall tracking, experience on all of the solutions I listed. And many of these solutions, unlike Graphene, do not depend on Google for their software & hardware. Do some of these solutions have flaws in their security & privacy? Absolutely. For which the thing they need is folks to join in to help fix these flaws. And I’ve been happy to see increased momentum across lots of these projects to do exactly that recently.