Steve Marx (via Peter Steinberger):
There are currently four SDKs for API v2: Swift, Python, .NET, and Java. We’re continuing to add new SDKs, so watch the blog for upcoming announcements. All SDKs and documentation for API v2 are managed via a code generation process, which means that they’re consistent across languages and easy to update as we add new API features.
[…]
Developers have often asked us to support the notion of a file ID: a unique identifier for a file that remains constant even when the file is moved. We’re pleased to announce that API v2 includes this highly-requested feature. Developers can now use file IDs instead of paths to make sure their apps don’t lose track of a file when it’s moved by a user.
You could call the old Objective-C API from Swift, but the new API does not work from Objective-C.
Update (2015-11-05): Matthew Abbot:
FWIW, objc support is planned as soon as the swift API leaves beta. There are a few aspects that will need a compat layer.
Update (2015-11-09): This Week in Swift links to this thread, which makes it look like Dropbox didn’t realize what they were doing.