Kodi—It can connect to a media source via FTP, so I was able to effortlessly connected it to my online storage to download shows and movies from it to watch on the fly, and on my TV no less. Without that, it'd be a huge pain just to get the file onto my TV.

SmartTube—It's an ad-free YouTube video app for Android TVs, and it has Sponsorblock included. You could say it's YouTube Vanced for Android TVs.

Discord bots—I've setup my own personal Discord server (no other humans allowed in it) and set it up with various bots that do things ranging from posting tweets/ posts from Twitter/ Bluesky to letting me know when specific channels have uploaded a new video on YouTube or gone live on Twitch. I've also got another bot monitoring some RSS feeds.

The various wireguard mesh VPNs (along with Wireguard itself) such as tailscale/headscale, netbird, etc

Wasted (Android Only)

Can nuke your phone's data if not unlocked for X amount if time, along with many other triggers for a wipe.

Very useful considering the political climate of one of the most powerful nations in the world has someone done a nazi salute behind the presidential podium.

Warning: I am not a lawyer. You might get in legle trouble for using this app (Such as "Destruction of Evidence" charges)

Its a bit more than an app, but QGIS is like, actually amazing. Also GDAL (and PDAL).

Stremio + torrentio plug-in.

My wife and I haven't paid for a subscription in 5 years and watch everything we want

Krita

Syncthing

Aside from the obvious FOSS offerings, there is a ton of free music software out there, including plugins for your favorite DAW.

While we are at it, Reaper is not free but they are also not going to bug you to pay for it. It is so good and inexpensive that they mostly rely on the honor system for payment.

Dosbox

ScummVM

GZDoom

DevilutionX

Wargus

JDownloader

Fuck apps. Real people use programs.

ffmpeg

KiCad. GNU Linux. Blender. Gqrx. Rclone. Syncthing

I recently learned about an app called Snappy Driver Installer Origin. It's a minimal FOSS program that checks our PC for the drivers it has, needs installed, or updated and goes about it quickly. It's also portable so it's great if you want it on a install thumb drive.

There are so many apps out there that try to get you to buy or pay a subscription for this feature and others, so it's been a breath of fresh air for me to have learned about and use it.

Off the top of my head:

Krita

Handbrake

LibreOffice

There are so many complex applications that I can't believe are free: KDenLive, Gimp, Audacity, Firefox, Discord, Calibre, Jellyfin, Rainmeter, Godot, Retroarch

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