Can I Add an external Identity Provider with React Native or mobile app, I don’t see any documentation about this. Is this impossible with Okta?
Yes, a user can log into a mobile application via an external identity provider, but you will need to have them login through the Okta domain via redirect (you won’t be able to make API calls to Okta to complete primary authentication for these users). This is how our React Native Browser Sign In sample works, for reference.
You likely want to look into setting up an External IdP and adding buttons to the Custom Okta Sign In Page so users can login through these providers OR configuring Routing Rules so they are automatically routed to the appropriate IdP (via Idp Discovery which you can enable on the Okta-Hosted Custom Sign In Page) when they are enter their username in the Okta login page.
Ok I got it. Thank you @andrea .