Apollo Client 2.0 introduces significant improvements over its predecessor, enabling developers to manage client-side data and fetch from non-GraphQL APIs using the same query language. The new version boasts a revamped modular architecture that is 2–5x faster, 40% smaller, and allows users to upgrade by changing only a few lines of code. Apollo Client 2.0 features an improved cache system, which can be easily swapped out for custom implementations, as well as a powerful network stack called Apollo Link, allowing developers to hook into the request cycle at any point to manipulate data processing and retrieval. This enables the use of GraphQL to manage client-side data, local data, and even REST endpoints in a unified manner, simplifying application development and reducing front-end complexity for React, Angular, and Vue developers. With its modular architecture, Apollo Client 2.0 is designed to be flexible and extensible, allowing developers to tailor their network stack and cache implementation to their application's needs.