Linux

I'd say the terminal, although its not linux exclusive and kind of a cheat answer. Flameshot is also a staple for me, I use it everywhere.

MPV comes to mind, although its also available in windows.

Strawberry and 0AD are awesome

Emacs. Need I say more?

Perhaps a controversial opinion, but I quite like Mailspring as a desktop email client. It looks and feels much more modern than Thunderbird or Evolution.

Kasts for podcasts, since it sync with Gpoddersync on my nextcloud.

Spectacle always makes me smile with how easy and featureful it is for a screenshot app.

Okular is a better PDF viewer than any proprietary app I've used.

I really like the disk usage analyzer in gnome. The ui/visualization is really intuitive and useful, and I often wish for something similar on windows.

Cinnamon is hands down my favourite DE. I always see people talking about GNOME and KDE, to me Cinnamon is the best of both worlds. Strongly recommend it with the Orchis GTK theme, which is made for GNOME but works fine on Cinnamon.

My favourite graphical app in the more traditional sense is Firefox. If CLI apps are allowed, I'm a big fan of GNU Nano, a CLI-based minimalistic editor, basically Emacs Lite.

I really like Setzer. It does everything I need from a latex editor and looks much nicer than other editors I have used on windows imo

• Firefox
• Jellyfin
• (when I get it to work) KDE connect
• krita
• aMule
• riced xfce
• riced kde plasma

Micro. It's a terminal text/code editor that shares keybindings with modern text editors.

• patched dwm
• polybar
• kitty
• a ton of tui's (mutt, ncspot, cointop, btop, dry, etc)
• obsidian
• vscode
• rofi, thunar
• blender and daz3d (wine)
• discord, element

The only real piece of software I don't like is Zoom; it's the most badly behaved app I've ever seen. Suck my balls Zoom, stay in your own god damned workspace.

Does Hyprland count? It's so effortlessly slick

Neovim.

• vim / neovim
• Signal desktop
• thunderbird & evolution
• firefox & vivaldi
• VL frickin C!
• qbittorrent
• docker
• axel
• zsh & bash
• vscode
• wireshark
• Konsole / Terminator
• Standard notes
• xed or geany

I literally live inside the combo of

• #Firefox
• #Evolution
• #Emacs
• #Alacritty
• #GIMP

And very rarely leave the comfort of my cozy habitat 😁

At work, I'm "forced" to use a Mac but thanks to #FOSS I've got the whole combo setup on my work laptop too except Evolution sadly.

ShotCut

Carla and QJackCTL for me. So much easier than having to haul around all my amps, pedals, etc.

I guess it's probably also available for servers but the most innovative and interesting peace of software I used in years is Distrobox, I like the AUR and love Debian and Fedora so that's a bridge I have been waiting for!

The Caja file manager. Hell the MATE desktop environment in general is just perfect for me. Xfce is acceptable too, though the inclusion of CSD in recent Xfce releases has made me a bit more wary of it when it comes to theming.

I also use Waterfox as my browser. A Firefox fork that has the option to put tabs below address bar (where they belong imo) out of the box without needing to muck around with the userChrome.css file.

Well, the permanently open applications on my system are: claws-mail, Pale Moon (browser forked from Firefox), konqueror (TDE file manager), konsole (TDE terminal), and Aqualung (music player). Other good friends include kate, Inkscape, and OpenSCAD (despite its flakiness). And I get a lot of mileage out of DOSBox.

If the OP hadn't specified desktop software, I'd also name Portage.

• Blender for 3D modeling/sculpting + rendering.

• ArmorPaint for painting on 3D Models, but I learned recently about 3DCoat, and it has a Linux version…

• I like listening to Podcasts (while I work on my PC) with KDE's “Kasts”. Use my Nextcloud provider to sync my listening status on the Desktop with my Android Podcast App (AntennaPod) for a flawless continuation on mobile.

Zathura, Firefox, VS Code, Remmina, Virt-Manager, hexchat, drawing, Master PDF, PlayOnLinux+Wine, LibreOffice, GVIm, Pragha, XFCE Terminal (But font broken in Fedora)

urxtv

Easy Effects is such a great program. Very good for doing all sorts of effects on audio. Great for filters and EQ.

Nothing Linux only but:

• Firefox
• OnlyOffice
• mpv
• DoubleCommander

Pinta. It's like paint.net but works on Linux. Quick and simple way to edit images on Linux.

Definitely the clipboard manager. On kde, it's klipper. This is actually such an underrated piece of software that I can't live without. Windows has one too, but they added their's a little after all the linux desktop environments got one by default.

xpenguins

• Newsboat Lightweight, custom rich, with very cool look on terminal.
• Doom Emacs Very hard to use. But once you got it, nothin can beat its multi-function note!
• Freeplane Must have software to mapping everything you want perfectly and very lightweight brain-mapping.

Whenever I use gnome I install the material-shell extension. I love the tiling.