Hello, sorry I missed your post, the forum had never been used much, I was actually thinking of closing it.
Anyway, I still follow Flarum development once in a while, and I'm still liking it a lot, I was thinking of maybe making it a service for users who want to be able to host their own forum on a specific topic. We are too tight on resources right now, but another handful of users and I should be able to rent another server to host such service.
But I digress...
Yes, you can 'sync' your Seafile library on your Android phone! The app allows you to browse all your libraries (including encrypted ones) and you can consult / download from there as well. I am using the Seafile client from F-Droid and it has been working well pretty much forever. What kind of issue are you facing? Is the desktop client also having issues?
There is also optional WebDAV support, but it hasn't been tested for a long time (and doesn't seem to work right now).