How would you design and develop a mobile app for the Alumni.thebestmba.org community (feature ideas + tech stack)?

Hi all, I’ve been exploring the alumni.thebestmba.org site and thinking about building a companion mobile app for its alumni network.
The idea is to enhance networking, job sharing, events, mentorship, etc. — similar to how active MBA alumni networks help professional growth and engagement.

A few questions:

1. What core features should the app have (e.g., member directory, events calendar, chat, job board)?

2. Should we integrate real-time features (push notifications, live chat)?

3. What tech stack would you recommend for Angular/React + backend (Firebase/AWS etc.)?

4. How would you handle secure authentication for alumni only?

5. Any thoughts on monetization (premium features, sponsorships)?

Would love to hear ideas from both alumni community builders and app developers!