Building an AI Chat Interface in React Native with Streaming Responses Tap "send", wait three seconds, then a wall of text appears at once. That's the difference between an AI chat that feels alive and one that feels broken. Streaming — token-by-token rendering as the model thinks — turns a slow API call into something users perceive as a conversation. On the web, the Vercel AI SDK and useChat make it almost trivial. On React Native, you have to think harder: there's no EventSource in the runtime, FlatList can't be naïve about re-renders, and Markdown doesn't render itself like it does in the browser. This post walks through a production-ready streaming AI chat in React Native and Expo end-to-end — server endpoint, client wiring, and the mobile-specific gotchas (network drops, scroll behavior, persistence) most tutorials skip. Stack: Expo SDK 54+, React Native 0.81, the Vercel AI SDK ( ai v4.3+), and any major LLM provider — Anthropic Claude, OpenAI GPT, or xAI Grok via the @ai-sdk/* adapters.…