What should go in your first release?
Start with one task a user can complete from beginning to end.
Pick one useful task
For a booking app, that might mean choosing a slot, entering details and getting a confirmation. Build that complete flow before adding dashboards, loyalty schemes or a long list of settings.
Connect the real systems early
If the app needs a payment provider or an external API, connect it in the first release. Use a sandbox where possible. Test errors and timeouts as well as successful requests.
Write down what “done” means
Agree the acceptance criteria before writing code. Include validation, permissions and error messages. Decide which browsers and devices need testing, and what should happen if a dependency is unavailable.
Watch someone use it
Ask a few people to complete the task without coaching them. Note where they get stuck. Fix those problems before adding more features. A smaller release gives you fewer things to debug and clearer feedback.