I use one called X-Plore. It’s actually very good. Even has a WiFi server, conpressed archive support, etc. but the downsides are that it’s close sourced and some features are behind a paywall (though IMO they are worth it).
So I was thinking of moving to some free or open source software. Any recommendations?
I have been using FX File Manager along with the stock file manager apps for some years.
Although FX is not open-source and hasn’t been updated since 2019, it is working well so far without any issues on Android 11 (OneUI 3.1) and it has no trackers/ads and completely respects your privacy.