Managing sensitive files with a server.

[Cross-linking for reference: https://stackoverflow.com/questions/34928673/can-i-upload-files-from-a-custom-website-form-to-dropbox ]

It sounds like you want to build an app that only connects to a single Dropbox account. The API was designed with the intention that each user would link their own Dropbox account, in order to interact with their own files. However, it is technically possible to connect to just one account. The SDKs don't offer explicit support for it and we don't recommend doing so, for various technical and security reasons.

However if you did want to go this route, instead of kicking off the authorization flow, you would manually use an existing access token for the account and app. (Just be careful not to revoke it, e.g. via https://www.dropbox.com/account/security .)

On the StackOverflow question, one poster recommended using the JavaScript SDK for this, but note that doing so would expose serious security issues, like I mentioned above. Instead, you could handle the integration server-side only, which would allay most of those concerns. In that case, I would recommend using an official SDK for your platform, if possible, or using a third party library, or the HTTP interface itself:

https://www.dropbox.com/developers/ 

Work through the tutorial and documentation for whichever you end up using to see how to upload files. The important thing is to make sure you only keep the access token on the server, where the end-users won't have access to it. That does mean however that the uploaded files would have to go through your server before going to Dropbox though.