Synctrain is an open source (MPL2.0) iOS Syncthing client (which I made) with full native mobile-first UI and tight iOS integration (shortcuts, background processing, etc).
You are most likely in France: your government does not allow publishing an app containing cryptography (in this case, Golang's crypto implementations and a package used by Syncthing - only using iOS libs should be fine) without authorization (which can only be obtained through French forms, at which point I'd want a French lawyer to be involved, so no).
You could of course build the app yourself from source.
Similarly, Trixie contains an updated version of Dovecot that (even though the version number seems to indicate otherwise) has a new configuration format that is not backwards compatible. This is clearly stated in the release notes but may be surprising nevertheless.
So, basically any local productivity tool, saving files in a synced folder.
While this works, Syncthing does not really provide anything for fine-grained collaboration or sharing (you only share full folders). Encrypted peers do allow storing files on a machine that you don’t have to trust.
Any tips for an app to use on iOS to capture the necessary .ply data?
Scaniverse is a great app by Niantic that can do this on-device, but it isn't very customizable and can't export its raw scanning data (exported .plys do not have the data this editor requires).
In my neighborhood (Netherlands) it appears the fiber network is physically point-to-point (subscriber to ODF), but is operated as XGS-GPON (so all subscribers see the same light signal so to say, but each over their own ptp fiber from the ODF). So point-multipoint only at the active layer.
I was told that this is because the company who is rolling out the fiber wants to make the network as attractive as possible to ISP’s who want to offer services over it (and wants them to compete) which may be more difficult in an actual physical point-multipoint network (which requires PON). The ISP currently likes PON more than AON (basically Ethernet over fiber to a switch) because the equipment is cheaper. In theory I should be able to switch to an ISP who offers AON or its own PON (they’d only have to physically patch my fiber in a different port at the ODF).
This. ESPHome additionally provides a minimal form of "device management" for larger numbers of devices, including OTA updates of firmware. This is an often underestimated aspect of HA; having many devices of different types buried in your home's walls and ceilings will get cumbersome to maintain, update and replace very quickly.