I want to buy a new phone.
I value long battery-runtime and easily flashing of custom ROMs most.
ATM I'm thinking about OnePlus 7T, Pixel 3a or Fairphone 3.
Can anyone of you provide some opinions on those, or another alternative?
Note that IPhone is out of question, not only but foremost, because of money.

Haven't gotten the chance to try one myself, but shift phones allow custom software iirc

Realme 6
https://m.gsmarena.com/realme_6-amp...
Realme 6 - Full phone specifications ...

$260

Sony has an impressive commitment to development. Unlocking, rooting, and flashing are all very easy on their devices.

@heyheni rom support for realme 6 looks abysmal. Not worth buying.

im currently using oneplus 7 pro (guacamole). i wish i could lock the bootloader to secure it a bit, i can't use the 48 mp camera, only the 12mp one. the installing was easy, dont forget to delete your data after installing, you will run into a bootloop. its also a a/b device, so reboots wont take long.

@bahua didnt they removed the website to unlock the bootloader?

@stop

Unless they did it in the last couple months, no. The website is still up, for sure.

https://developer.sony.com/develop/...

Op7t is good option and there is so many custom roms available out there . Myself currently using apsip derpfest . It's running great . You can also flash pixyos . This ss was taken before I flashed derpfest . Gcam works perfectly fine. You may have to face issues like u can't enable op camera branding in op cam on custom rom .

You might face slightly poor connection in remote areas . Nfc may not work . ( I had to use a patch to get it work ) . You also might face earphone sound issue while phone calls. No issues with internet calls whatsoever .

Though ram management is good as default roms . For earphone call issue check forums . You'll find easy solutions.
Overall op7 series is great for daily drivers on a custom rom.