Yes, you can uninstall any cloud software for sources which you can link with odrive. For example, if you have Dropbox installed and odrive, the same files would exist synchronized locally within your dropbox folder and also within your odrive folder (though when they exist as placeholder files in odrive, they take up hardly any space). Since you don’t need two sync clients to the same backend, you could just use odrive.
With regards to available links, we already support a lot of different sources, in addition to common protocols such as FTP, SFTP, and WebDAV (which many cloud sources also support, so you can use these protocols to link to them). We’re constantly adding and improving upon support to more and more sources on an ongoing basis. You can add your two cents in for each source in the Feature Requests portion of the forum.
Files don’t exactly get converted to placeholders (unless you unsync them). It’s more like they start out that way. So when you first link a source, we think it’s wasteful to try to sync everything in it; some people have a LOT of stuff in the cloud. So we let you link and see what’s available quickly by showing you placeholder files. This allows you to only download and keep synchronized the files that you need.
You cannot drag and drop placeholder files from one cloud to another, but you can sync files from one cloud, and, once they are fully downloaded / local, you can move them into another folder that is tied to another cloud storage backend. This will effect the move operation that you want.
There isn’t an out-of-the-box deduplication feature yet, though you could potentially script something using the odrive Agent (a command line interface client).
For placeholders and whether or not you should trust the individual clouds… it depends on the cloud storage providers. For example, if you use Amazon S3, your files have multiple copies out in the cloud to ensure availability (you can even control this and the cost by using their reduced redundancy storage class). Dropbox has some knowledge of your content–maybe not direct knowledge, but some signature so they can deduplicate on their backend and also scan for copyrighted material… if you don’t like this, don’t use dropbox. Or use our zero-knowledge Encryption feature when using Dropbox storage. If you want to keep a local copy of everything, then just right-click --> Sync and select to download everything (free), including subfolders (free), and save the folder sync rule (paid). You really do have a lot of options.
The ability to unsync is only in the paid version, but there are ways you can revert everything back to placeholders if you need to (e.g. unlink and relink the source)… unsync and the other offerings in the paid Premium plan are an amazing deal when you add it all together, so we hope you find it useful enough that you will want to upgrade.