I am using OpenCamera, but would welcome suggestions: https://f-droid.org/en/packages/net.sourceforge.opencamera/
OpenCamera is so far the best that works. I often use the white balance settings, exposure settings, focus, and zoom. I tried another FOSS camera (I forget the name, not on F-Droid either) that supposedly have real-time filter, but it doesn’t launch on my phone.
So eventually I always use Darktable on desktop if I want to enhance my photos from my phone. Although depending on the scene lights as well, white balance settings in OpenCamera can be good enough to produce nice looking photo.
Seconding OpenCamera. Also, if you check off everything in Camera Preview (angle, pitch lines, etc.), you can pretend you’re in a fighter jet.
I am happy with the simple mobile apps suite on F-Droid, including the Simple Caméra app. The package name is com.simplemobiletools.camera I am not a camera power user though, and I only need basic functions. OpenCamera may be better; I don’t know.
I use many of the Simple apps, but not the camera for some weird reason. Thanks for the reminder, I’ll also send the developer a few bucks.
Open Camera is pretty high quality. I use it daily.
I wonder if there are any that rival the machine learning algorithms in the proprietary apps. I just use the bundled Pixel 5 camera app and the results of its Night Sight mode are impressive. It would be hard to give that up.