FolderSync is a application that enables simple sync to cloud based storage to and from local folders on the device memory card. It currently support multiple SkyDrive, Dropbox, SugarSync, Ubuntu One, Box.net, LiveDrive, HiDrive, Google Drive, Google Docs, NetDocuments, Amazon S3, FTP, FTPS, SFTP, WebDAV or windows share (Samba/CIFS) accounts, and support for more platforms are planned.

Effortlessly sync your files. Backup your music, pictures and other important files from the phone to your cloud storage or the other way around. It has never been easier. Tasker / locale support enables fine grained control of your syncs.

FolderSync also contains a full file manager, that enables you to manage your files locally and in the cloud. Copy, move and delete your files in your cloud/remote accounts. Support for creation/deletion of buckets in Amazon S3. Upload and download files from the phone. It's all supported.

IMPORTANT:
Google Drive is fully supported. Just select the Google Docs account type.
Dropbox authentication currently only works using a webbrowser, so please disable official dropbox app while validating account.

You could also try out the lite version, so you can test functionality before you buy. The lite version only allows one account and has no sync filters or Tasker support.

Follow news here:
http://twitter.com/#!/FolderSync

The full change log can be found here:
http://www.tacit.dk/foldersync/changelog

Get support:
http://www.tacit.dk/support

Please read the FAQ. I have addressed most comments there:
http://www.tacit.dk/foldersync/faq

Detailed description:

You can choose any folder on the memory card to sync. Currently one-way and two-way sync are supported. Sync intervals and other sync settings can be specified for each sync item you configure. You set up a folderpair to sync and it will automatically keep your files in sync.

Current supported providers:
☆ Amazon S3 Simple Storage Service
☆ Dropbox
☆ SugarSync
☆ NetDocuments
☆ Google Docs/Google Drive
☆ Box.net (WebDAVs)
☆ LiveDrive (WebDAV/FTP)
☆ HiDrive (WebDAV/FTP)
☆ FTP
☆ FTPS (SSL/TLS implicit)
☆ FTPES (SSL/TLS explicit)
☆ SFTP (SSH File Transfer)
☆ Samba/CIFS/Windows Share
☆ Ubuntu One
☆ WebDAV
☆ WebDAVs (HTTPS)

Current features:
☆ Instant (full version)
☆ Multiple accounts (full version)
☆ File manager - manage your cloud files
☆ Amazon S3 Client Side Encryption support
☆ Tasker/locale support (full version)
☆ User defined sync filters (full version)
☆ Sync to and from you selected provider
☆ Two-way sync with support for deletions
☆ Backup/restore settings
☆ User specified sync interval or specific sync times
☆ Choose connection types for each sync item
☆ Support for syncing of subfolders
☆ Sync of hidden files can be disabled
☆ No ads (full version)

Deletion in two-way sync:
To enable deletions in two-way sync, the option “Preserve target” must be unchecked

FTPS/FTPES servers without resume support:
Use these at your own risk, as uploads may become corrupt.

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