As far as I know, there's no official way of using Devise over a REST API. It is designed with a server-side Rails app in mind. There's devise_token_auth and related client libraries, but I wish there was an official way for handling authentication for single-page apps. Every time I look into this issue, it seems like there isn't much going on in this space. Then again, maybe the entire authentication protocols space is like that, and it's actually Devise which is in the unusual position of being a de-facto standardized way to do auth in the Rails world.