High-Level Documentation: Sync Solution or Remote File System

Hi Frank, I don't believe we have a document like what you describe, but I'll be happy to help with any questions you have about the API.

It sounds like you mostly have the right understanding here though. API v2 offers a different sort of interface than the old Sync SDK did (which was built on API v1). API v2 does offer a more direct remote filesystem-like interface, whereas the Sync SDK offered a local syncing abstraction (built on top of the remote filesystem-like API v1 interface). 

In API v2, this gives you more control over exactly what gets synced and when, but it does mean things like automatic local caching and polling aren't automatically implemened for you. I'll send this along as a feature request though.

So, if you're building on iOS, we recommend using an official SDK. We have one for Swift (as you mentioned) as well as one for Objective-C. The documentation there walks through how to set up and use the basic functionality for each.

You don't need to continuously re-download unchanged files though. The SDKs offer ways to know if/when things have changed. For example, in SwiftyDropbox you can use listFolder and listFolderContinue to get file/folder listings, and listFolderLongpoll to quickly know when something's changed. And you can use FileMetadata.rev or FileMetadata.contentHash to check if the file has/hasn't changed since you last saw it.

By the way, if you need more time to migrate your app to API v2, we can offer an extension for access to API v1. To request that, please open an API ticket with the relevant app key(s).

Hope this helps!