My requirements were integration with rclone and FolderSync (android app) to work natively with their APIs and it works like written on the tin. I was able to use rclone on a cloud server to transfer data out of Google Cloud (rclone can act as a local proxy to copy between services) and I'm able to use FolderSync on my mobile to keep it backed up.
The pCloud branded mobile app is OK (nothing great), the webapp works well (again, just sort of works) and so far I've found no real problems with it - no failed syncs, my backups are backing up nicely, it just sort of works without fanfare.