Dropbox, rsync, Acronis Cyber Protect Home Office, FreeFileSync, Duplicati, SyncBack, Microsoft OneDrive, GoodSync, Spideroak One Backup , BackBlaze, Dropsync, Second Copy, Unison File Synchronizer, Yandex Disk, Directory Compare, ozSync, Rsync Wrapper, rsync backup for Android, Backuplist, Immortal Files, 7zbackup, JFileSync, SynchroHajzel, Gmail Drive are some alternatives to Qtd Sync.