i mentioned in the tags that i tried out a Bunch of FOSS apps and can give recs if people want them - so for the audience of @oceanlandworld -
(disclaimer upfront, I'm not a tech person, I just like fiddling with apps)
Fennec (a firefox version)
Cromite* (if a specific website insists on being displayed in a Chromium browser
Tor Browser* if you wanna be extra sneaky - very slow though
as for search engines, Brave Search works well, I've been trying out a few different SearxNG instances with varying results. Qwant (based in France) or MetaGer (based in Germany) are good for European languages. Startpage for the most google-y results if in a pickle.
*iirc, those two weren't downloadable via F-Droid and I had to go look online. but also I genuinely only ever use Fennec, the others are "just in case" ones
Proton is the big one, obviously
for non-proton mail addresses, nothing beats FairEmail. can get fiddly if you care about UI, but works well if you use it the way it looks right when you download it too
AntennaPod for podcasts - straight up the crème de la crème for me, does everything it's supposed to and the UI is customizable to an extent
Metro or Auxio for local music - I personally use the former, but the Material You design of the latter is more well-liked by some
If you use Spotify or YouTube Music or something and don't want to just search for the cracked apk, I used OpenTune briefly before I put my own music library on my new phone. It's a YouTube Music client and worked like... fine. I just dislike streaming, personally. But also, you should have your own music
Audio Tag Editor - not a FOSS app, but if you download music sometimes and need to edit the tags on something because your very legal download thing messed up, it'll do nicely, and I haven't encountered a single ad
Fossify Calendar - calendar app. Etar and Proton Calendar are great alternatives too
tasks.org - for tasks and ToDo's. you can add tags, places, subtasks etc
p!n - if you're anxious about forgetting something important and would like to have it displayed in the status bar
Standard Notes - for note taking
If you'd like to combine notes & tasks in one single app and don't mind not having a widget available, Joplin is great too
Chrono - to replace the native clock app. has a stopwatch and timers too. alarms work well, i was anxious about that because I'm a big oversleeper, but no issues. it also let's you set separate tasks like lil (or big) math problems or a memory thing in order to turn off alarms, and you can adjust the volume for each separately
Librera FD - PDF & audio book reader, allows some very basic PDF editing
Organic Maps - as an alternative to Google Maps. granted, it doesn't do everything gmaps does (e.g. public transport connections). And you have to download your regions' maps, which wasn't a problem for me (Switzerland is tiny) but might take a while for like, the US. For what I need maps for ("how long does it take from there to there, what was that street called, uhhh am I lost??") it's enough.
NewPipe - remains my YouTube alternative. you can subscribe to channels, make playlists, and download any video or audio
RedReader - the reddit client I use. i only go on reddit if I have A Problem and don't use it actively myself, but you can make an account there, I assume you could also log in with an existing one
systems stuff / general replacements for native apps:
Fossify is my best friend, I <3 Fossify.
Fossify Phone as a dialer
Fossify Contacts for contacts
Fossify Calculator for those difficult math questions your alarm clock might throw at you
Fossify Camera - disclaimer, I use this one as my main one, and it's enough for pretty much everything I ever need a camera for, but the quality is nowhere near as good as Samsung's camera. 3rd party apps can't always access Special Functions etc etc. I kept Samsung's camera installed, and if I ever want to be Very Aesthetically Pleasing, I'll use it. Otherwise it gets ignored.
Fossify Gallery - literally does everything a gallery needs to do
Fossify File Manager - instead of Samsung Files or whatever
Fossify Voice Recorder - works well, if you need a recorder
QUIK - for SMS. Fossify Messages is a good alternative
HeliBoard - keyboard. Fossify's keyboard or AnySoftKeyboard are great too, I just like making my keys neon yellow at day and dark purple at night, and HeliBoard lets you customize everything
obviously if you want to get rid of Google as much as possible, get a Proton email address
the rest of Proton's apps all seem to work well too; I tried out the calendar (but personally liked Fossify's better) and use their VPN and password manager; I can't speak much to the rest
Shelter - an app that lets you set up a separate Work Profile. i did that and shoved Outlook, MS Teams and the MS Authenticator which I need for work in there, deleted these apps off my personal profile and can now put the work profile (with all its apps) to sleep whenever I don't need that stuff
cobalt.tools - open source website that lets you download almost everything from online sources. Seal is a FOSS app that does the same
Kvæsitso - my current one. search-focused, though you can pin favorites and work with assigned tags. open source! supports widgets.
Niagara - what I used with my old phone (rip, love). alphabetized list with a couple pinned apps always visible
both of these helped shorten my screen time bc you don't just swipe through screens staring at apps and widgets.
random notes in case this is useful for anybody:
As a general rule: Everything your phone lets you uninstall is Safe to uninstall. Everything it lets you disable is Safe to disable. You're not gonna break shit; everything to do with important system functions will be protected by a greyed out "disable" button. Hell, some of the stuff that Would be safe to disable, you won't be able to, but I found most of that stuff doesn't even show up in the apps drawer and is easy to just ignore.
I haven't had any issues with any of the apps mentioned, but for replacements of native apps in particular I'd recommend to err on the side of caution and try out the new app while keeping the native one active as a fallback; that's what I did with the clock (and my 20 alarms) in particular. For phone & messages, I set the new ones as default and asked people to call/message me.
If native app replacements seem to work out, I'd still recommend only disabling the native ones and not deinstalling them (most you can't these days, anyway).
If you want, go into your setting, into 'Permission Manager' and go through your app list, revoke everything you think those apps don't need. I revoked very aggressively and nothing broke or suddenly didn't work anymore (it's unlikely to, anyway, it'll just prompt you to allow xyz again if you try to use anything and it can't due to revoked permissions.) I also started using "allow just this once" a bunch more. Lol ask again next time, sucker. Beg me.
I turned off Location on my phone, personally. Idk if that's something people Do already, but well worth doing imo. If I desperately need navigation help, I briefly turn it on and then just right back off.