[antocv]

Battery usage is basically zero, since I schedule it to run during evenings and night-time when it is charging with the termux-scheduler-thingie. Android wakes the script up, when those conditions are met, no battery waste. The script when waken up - it checks if the file left over from last time is older than 1h, if so continues to sync, otherwise exits.

Setup of a ssh connection is similar to https, rsync exchange of rsync is usually "all good" and thats it. Rsync otherwise is a very efficient but not very documented protocol network-bandwidth-usage-wise.

Mesh? Syncthing, tried it, sucked for reasons I cant remember now. Nextcloud - had it for years, mind you I was contributed to nextcloud the android app, fixing many bugs, but still it caused me data loss / picture loss. Which I only found out after implementing the rsync solution and seeing OMG rsync found so many pictures Nextcloud was supposed to keep in sync for the past year but it just bugged over.