There is an Android Syncthing fork [1] which is active and 1.3K stars (for whatever that's worth).
"Planning to close my Google Play Developer Account. Please say hi if you are interested in obtaining the latest gplay release files from me to help in publishing this app."
I think for the people interested in using Syncthing rather than Dropbox or Google's syncing option, that's not _that_ much of a problem.
It's in the description on GitHub. Get F-Droid.