Choose an interface deliberately
REST and GraphQL offer different approaches to requesting data. Consider the client’s needs, the team’s experience and the systems already in place. Document requests, responses and errors. Use pagination and appropriate caching for large collections, and verify behaviour on slow or interrupted mobile connections.
Enforce access and validation
Authentication identifies a user, while authorisation determines what that user may do. Validate requests on the server and avoid trusting client-side controls alone. Limit abuse where appropriate and keep sensitive values out of public logs. Test denied access and expired sessions as part of the product journey.
Manage change and performance
Mobile clients can remain installed while the backend evolves. Plan compatibility, versioning or a clear migration strategy. Monitor errors and latency, and use representative data in performance checks. A documented API and predictable failure behaviour make implementation, support and future integrations easier to maintain.