We have our Moodle site behind an authentication proxy, which utilizes SSO/LDAP on the backend. Because of the proxy, the Moodle Mobile app can't get to the server itself without jumping through some hoops. My question is this: what endpoint(s) should I make available through the proxy in order to allow our students to use the Moodle Mobile app? We are running Moodle 3.3.3+.
what is happening when you try to connect to your site? are you able to reach the credentials (username/password) screen or you don't even get to that page?
When you are using SSO/LDAP you should set-up your Moodle app to force authentication via the app, see https://docs.moodle.org/34/en/Moodle_Mobile_guide_for_admins