KeePass currently supports FTP when opening .kdbx file. It's not enough because cloud storage is much more common nowadays when people share files between multiple devices.
I propose a feature to open .kdbx file in cloud such as Dropbox, Google Drive, etc, and save to the cloud directly so avoid revision conflict and save revision control operations, which, usually, cause losing critical information in KeePass.
The KeePass program does not include application dependent features, but application specific features can be implemented via plugins (mostly third-party). See KeePass plugins Backup & Synchronization & IO for plugins that might meet your needs.
I'm using cloud sync plugins but the issue is still there that the plugins can not download the latest revision automatically before opening .kdbx file. So I will be opening an out-dated local .kdbx file if I'm running KeePass on a computer w/o cloud storage software installed.
The worse thing is that, when I update the local .kdbx file, the plugin will upload it to cloud and likely overwrite the new items uploaded by another device.
In a word, backup/sync plugins will not being able to resolve the revision conflict issue - esp. when you running KeePass w/o cloud storage software installed, which usually, is prohibited by IT security policy in some companies.
Last edit: meokey 2014-08-26
I am confident that KeePass developer will not implement application dependent cloud service access features directly in KeePass unless the access is standards based (e.g. http, ftp, webdav etc...) and not proprietary API based (e.g. Dropbox access protocol). Your best option is to find a way to work with the current KeePass version and the particular KeePass plugin capabilities.
Limitations or help with plugins should be addressed on the particular plugin forum, if one exists. You best bet for help with KeePass features is the KeePass help forum. I am not familiar with the specific features of each Backup & Synchronization & IO plugins, but there are at least three plugins that claim sync capabilities with online storage services and an additional plugin that claims databases can be opened and saved directly to the cloud. It seems likely that at least one of the plugins or a plugin combined with KeePass sync can merge changes in the cloud copy of the database with changes in a local database.
Note: KeePass synchronization, unlike cloud based file replication, can merge differences between the most recent and less recent copies of a database.
Last edit: wellread1 2014-08-26
Thanks wellread1. I found KeeCloud may sync/open/save with S3 and Dropbox. It's good enough as I can use other plugins to backup to other cloud storage. Thanks.