Also in fdroid if you add the github releases as a repo.
I actually wasn't aware of this, you've made my day. Thank you!
I sync my journal directory using syncthing and it works reasonably well.
I had the opposite experience with Syncthing + Logseq. The way Logseq is designed, refreshing the entire graph is a must before you even consider editing your pages in another device. I forgot to do it once and after some time editing my pages, I realized that I lost a good chunk of my notes from several days back.