How can I store the session cookie in my native iOS app ?

I want to be able to close my iOS app, re-open it, and still be authenticated. To do this, I need to store the session cookie, but I have no idea how to access it from the Swift codebase.

Can I, for example, intercept the WebSocket messages, read the session cookie to be able to store it ?

Websockets don’t have the concept of cookies.

The cookie is sent on the initial http request that is done before establishing the websocket connection. Extracting cookies from http response headers should be trivial in any languages.