We'll start by creating a fully-featured API in just a few minutes with API Platform, Symfony and Doctrine. The API will support pagination, data validation, access control, relation embedding, filters and error handling.
It will expose many formats (JSON-LD, Hydra, JSONAPI, HAL, JSON, XML, YAML and CSV), will be documented with Swagger/OpenAPI and will have a nice UI done in React.
Last but not least, the API will respond in a just few milliseconds thanks to its builtin invalidation based cache mechanism.

Then, we will use the ReactJS tools provided by the API Platform to consume the exposed Hydra documentation.
In a few more minutes, we will get a Material Design administration interface (a la Sonata / EasyAdmin - but 100% client-side) built with React.
Finally, we'll discover 2 nice code generators to bootstrap a SPA (React, Redux and React Router) and iOS and Android mobile apps (React Native).