What problem does it solve? Mobile developers often struggle with inconsistent server state management, token refresh handling, and scattered error handling in React Native apps. This Skill provides standardized patterns for the entire data layer so queries, mutations, and local stores behave predictably. ## Core Features & Use Cases - Server State Management: Standardized TanStack Query setup with global error handling, query key conventions, and mutation patterns with automatic 401 handling. - API Client Conventions: Typed API wrapper with snake_case/camelCase transforms, automatic response unwrapping, and token refresh via expo-secure-store. - Local State with Zustand: Patterns for coin, streak, and notification stores that sync with the backend on app launch. - Use Case: When building a new exam-listing screen, apply the query hook pattern with the correct queryKey format and let the global error handler manage auth failures instead of writing per-screen try/catch blocks. ## Quick Start Apply the mobile data patterns to create a TanStack Query hook and Zustand store for a new feature in the React Native app.
