Here's my non-cli list of to me usefuly software on linux (working as freelancer since 2010):

- Webstorm + Phpstorm: Amazing tools for web development

- Sublime text for simple text editing

- Meld for graphical diffs between files and directories. Very useful.

- Signal client: Using it more and more recently

- Spotify: That's not productivity though :)

- Joplin for markdown formatted note taking

- KeepassCX + FF extension: Works decently for password management. Though there's no solution for FF mobile as far as I know.

- Reaper for professional audio production (never liked audacity and ardour). There's also Bitwig which is more like Ableton live but quite expensive.

- Gimp: I use it but I don't like the user experience.

- Inkscape works pretty well for anything vector based

- Libreoffice: I tend to use calc regularly

- Darktable for raw image editing

- Arduino

- Figma for digital design (web-based, so not really linux)

- Nextcloud as file storage and for synching contacts and calendars.

- Zoom for video conferencing (need to try jitsi again though)

Not sure what mobile platform you use, but on Android I have been very happy with Keepass2Android (https://github.com/PhilippC/keepass2android). It uses the android password-manager API so you get autofill (or at least a quick-access button) on login fields in both apps and websites.

Edit: It also supports a lot of methods for syncing the keepass database between devices, I point it to a directory that's managed by Syncthing and it works pretty flawlessly.