Lyx
It combines the advantages of Latex with the ease of use of LibreOffice.

GIMP
It has some rough edges (fewer than it used to), but it's all I need for editing my photos.

Darktable
A fully capable Adobe Lightroom alternative

cmus
A TUI music player that plays music. Nothing else.

And of course VLC and Firefox, which aren't just the best FOSS programs for their use case, but the best, period.

Kind of niche but Guitar Pro. Not sure what the newer versions are like but the one I have is great for composing and arrangement.

I'd probably say Steam or VLC player.

foobar2000 - My primary music player since 2012

gcc

Well till my Windows 10 machine died, it was Reason. Reason is an all in one DAW. Program, record, mix and master with super tactile graphics and an intuitive layout. Been two years without. I miss it.

OurGroceries.

The year was 2010, and the iPhone was not yet available where I lived. I could have bought one, and I could have activated service with it, but I would never be able to use it at home or anywhere around home. So it would have been pointless. I wanted one. Android was cool, but it wasn't really what I wanted. Wife needed a new phone, and our carrier had a deal. Two Android phones for $100, and each came with a $20 Android Market (what Google Play Store was called then) gift card. So yeah, we took that deal. The phones were ass, but I was able to put CyanogenMod (now called Lineage) on them and make them a little better.

We wanted a grocery app, and we discovered an app called OurGroceries. Free with ads, or $5 to remove the little banner at the bottom. Even without paying, it offered synced grocery lists and even Web access. As in, my wife is at the store and I'm on the computer, I just hit the bookmark and add something to the list, she sees it in a second or two (provided she has signal or WiFi). We both paid. The app was useful and it was nice.

When I got an iPhone, I immediately paid the $5 again. They since changed it to where only ONE person on the sync account needs to pay. That is to say, if you and five family members all download it, all six of you get ads. But if ONE person connected to the sync account pays, the paid status syncs and nobody has ads. That said, I'm not mad because $10 of the $15 I've paid wasn't even mine to start with, it was on a gift card. It's been 16 years, and we still use it.

Is it the best grocery app? I think it still ranks highly. Personally I think the one in Paprika is a little better. Our first requirement is that it must support iPhone, Android (my wife still uses Android), and computer. Paprika checks those boxes — so does Google Keep, which is another good option (that is also free!). Apple has shopping list support in Notes, and our computers are Macs, so that works, but Apple Notes doesn't really work on Android. It actually does, I think, through the browser (since my wife has an Apple account, on the Mac and on her iPad), but it's not as robust if you actually have an iPhone. Any note taking app should work, but the sync won't be there.

So if you don't want to pay, Google Keep should be your first stop. If you don't like Google for privacy or whatever reason, you'll probably have to pay. OurGroceries is either a single developer or a small team, and they're independent, and deserve at least the $5 they're asking for a whole family to use their app indefinitely (as long as they keep the server up — I hope, should they ever decide to take their server down, they allow a self-hosted option). If you want more features, Paprika is definitely a solid choice, but you'll want to wait for a sale. Normally it's like $10 on phones and $20 on computers or something. But it's actually not a shopping list app. It's a recipe manager that has a shopping list and a pantry inventory. And a couple other things. (OurGroceries also has a recipe manager, but it's not great, it's really just another kind of shopping list that can be copied into an actual shopping list — you can have multiple.)

Papyrus on my android. It's not even in the playstore anymore, but i keep -and backup- apk's. It's just the simplest notes app, without any markup. It saves as simple text files.

I just open it, jot something down, and leave it. Saves automatically. It might be way more than 10 years even, 15 plus years?

Steam

Firefox

VLC

Winamp

Notepad++

Unpopular opinion here: YouTube

Note: Been using it through my Brave browser and also without any account. Hence, why I'm still loving it

WinRAR. Probably over 20 years by now.

AntennaPod on my android. An open source podcast player with no ads that has all the features I need to enjoy podcasts.

• 7zip
• Firefox
• LibreOffice
• Various Linux distros, but mostly Ubuntu variants and Raspbian
• Cura
• OpenVPN
• Blender
• Gimp
• Windows - sorry everyone, it just works, but I stopped at 10.
• VLC
• Virtual Clone Drive

On Windows machines probably since more than 20 years: TotalCommander

Wish they would offer a linux port. (Though Krusader is quite a good replacement.)

Tweakybeat for the iPhone. One of the first music apps to come out on iOS. I bought it before I had an iPhone - to play with on the test phones at work.
It’s a monophonic sequencer with a single noise source which can be tweaked to make drums, beeps, swoops and gurgles. Such fun and always go back to it for a quick bleep session ever so often