FTPSync is a backup and sync application that automates the process of backing up and synchronizing data between two or more remote locations. It supports FTP, FTPS, SFTP, and WebDAV protocols, allowing users to securely transfer files between a local and remote server. FTPSync also supports versioning of files, allowing users to store multiple versions of a file in case an older version needs to be recovered. It also features an easy-to-use interface and allows users to set up scheduled backups and synchronizations. With FTPSync, users can ensure that their data is backed up and synchronized regularly, reducing the chance of data loss and ensuring that their data is always up-to-date.
FlowCloud discontinued due to storage and maintenance issues. Read more here: https://flowcloud.xyz/why.html
Discontinued site no longer available
Discontinued It appears that the service is no longer updated since 2012 and the iPhone app is no longer available. You can still register new accounts and the website seems to work.
Discontinued "The Syncany core team is on hiatus for an indefinite period of time". See https://github.com/syncany/syncany