Hardware far outlasts software in the smartphone world, due to aggressive chronic designed obsolescence by market abusing monopolies. So I will never buy a new smartphone - don’t want to feed those scumbags. I am however willing to buy used smartphones on the 2nd-hand market if they can be liberated. Of course it’s still only marginally BifL even if you don’t have demanding needs.
Has anyone gone down this path? My temptation is to find a phone that is simultaneously supported by 2 or 3 different FOSS OS projects. So if it falls out of maintence on one platform it’s not the end. The Postmarket OS (pmOS) page has a full list and a short list. The short list apparently covers devices that are actively maintained and up to date, which are also listed here. Then phones on that shortlist can be cross-referenced with the LineageOS list or the Sailfish list.
So many FOSS phone platforms seem to come and go I’ve not kept up on it. What others are worth considering? It looks like the Replicant device list hasn’t changed much.
Browsing on a phone or with Debian works ok for me with Firefox, though I don’t like Firefox that much.
I found Organic Maps preferable to OsmAnd but neither are that great. It should be possible to do something reasonable without a lot of CPU demands, given how dedicated GPS map navigation devices existed ih the early 2000s.
Yes if you ditch Youtube and anything else that requires modern codecs, that solves another issue. I’ve found Newpipe has broken a few times but it usually works, so that is what I use.
Modern apps and games (requiring GPU even) are another story, but let’s assume you don’t want to run them.
This leaves the question: if you want a BIFL smart phone but you don’t want to make phone calls with it, don’t want to run a web browser, and don’t want to watch videos on it, what DO you want it to do?