@User , let me try and explain what cookie_domain is. Basically, you have a client (your react native app) and your server (your nodejs APIs). Your nodejs APIs are accessible via some URL. In your local dev environment, that URL can be http://127.0.0.1:400 or http://localhost:400. In your production environment, that URL is https://yourdomain.com. Now, cookie_domain is a feature that answers the following question for the client (your react native app) - "I am about to send a request to https://abc.com, for each cookie I have in my storage, which ones do I send?" In this case, only cookies that have the cookie_domain as "abc.com" will get sent. So likewise, if in your dev environment, if your nodejs APIs are accessable via http://127.0.0.1:4000, then only cookies with the cookie_domain as "127.0.0.1" will get sent to it.