The main thing I use for ad hoc file transfers is Total Commander for Android (https://www.ghisler.com/android.htm https://www.ghisler.com/android.htm). It can

The main thing I use for ad hoc file transfers is Total Commander for Android (https://www.ghisler.com/android.htm https://www.ghisler.com/android.htm). It can copy files to and from a WebDAV inbox on the local network as well as my home directory (although the SFTP plugin I use for that is fiddly to set up and a bit buggy). For copying the same things on a regular basis, I run rsync scripts in Termux (https://termux.dev/en/ https://termux.dev/en/). They push photos from my phone to my computer and pull essential backup from my computer to my phone. They also synchronize themselves and Termux configuration. For exchanging files without a direct network connection, I have croc and the Rust version of Magic Wormhole (https://github.com/magic-wormhole/magic-wormhole.rs https://github.com/magic-wormhole/magic-wormhole.rs) installed in Termux. It may seem arcane and archaic, but I have found this setup better (more predictable and more reliable) than anything "mobile-native". I appreciate that Termux behaves mostly like other Linux machines. I had a pretty positive experience with Syncthing for Android on my previous phone. It was before I started using Termux. I had a directory called "clipboard" that synchronized between my desktop, laptop, and phone. Sometimes it took a while to notice new files. I would use it if I didn't use Termux or if I needed to keep multiple mobile devices in sync. If I had to often send files to a mix of Android and iOS devices on the same local network, I would try LocalSend (https://localsend.org/ https://localsend.org/).