What Features Are Essential for a Scalable On-Demand App

I’m planning an on-demand mobile app and want to understand which features should be prioritized during the initial development.

The app may need customer accounts, service-provider profiles, bookings, location tracking, online payments, push notifications, and real-time status updates.

For developers who have worked on similar apps, which features should be included in the first version, and which can be added later?

Also, what technical considerations should I plan for early to avoid performance or scalability problems as the number of users grows?