Expo SDK 53: The New Standard for AI Mobile Apps

By Malik Chohra

With the release of Expo SDK 53, the toolkit for building cross-platform React Native applications has reached a new maturity level. But specifically for AI-first mobile applications, SDK 53 introduces three foundational improvements that solve the biggest pain points of 2025: rendering complex Markdown, maintaining 60fps during intense LLM streaming, and standardized fetch implementations.

DOM Components: Finally, Rich Text & Markdown for LLMs

If you've built a ChatGPT clone in React Native natively before, you know the absolute nightmare of rendering LLM output. AI models return Markdown featuring complex tables, nested lists, inline math equations, and code blocks. Translating that via a native Markdown-to-React-Native-Text parsing library is slow, buggy, and rarely supports syntax highlighting perfectly.

Expo DOM Components solve this by allowing you to embed actual web components directly into the native hierarchy using WebView under the hood, but with synchronous React messaging.

// Render perfect Markdown exactly like the web
import { DOMComponent } from 'expo/dom';

export default function AIResponseBubble({ markdown }) {
  return (
    <DOMComponent>
      <div className="prose prose-sm font-sans">
        <ReactMarkdown>{markdown}</ReactMarkdown>
      </div>
    </DOMComponent>
  );
}

This allows us to use strong web libraries like react-markdown and prismjs to render gorgeous AI responses identical to the web app, without sacrificing native navigation.

React Compiler: Free Performance Gains for Heavy UIs

AI apps are notoriously state-heavy. When streaming a response from Claude 3.5 Sonnet at 40 tokens a second, you update React state 40 times a second. In SDK 52 and below, this required massive manual injection of useMemo and useCallback to prevent the entire chat screen from re-rendering and freezing the app.

SDK 53 aggressively pushes support for the React Compiler. By enabling this compiler, React automatically memoizes components.

• No more redundant re-renders of older chat bubbles when a new one is streaming.
• Battery consumption during long AI generations drops by up to 30%.
• Developer velocity increases because we don't have to manually optimize dependency arrays.

Fetch API Upgrades for Streaming (SSE)

Prior to the recent React Native core updates included in Expo 53, the standard fetch() API on mobile did not properly support handling streams. Developers had to use cumbersome polyfills like react-native-fetch-api or rely on native WebSocket libraries to build low-latency AI pipes.

Now, Server-Sent Events (SSE) work out of the box using standard Web APIs. You can parse the response.body.getReader() stream natively, making integration with OpenAI's and Anthropic's streaming SDKs nearly identical to Next.js.

Conclusion

Expo SDK 53 isn't just a version bump; it is the version that makes React Native the undisputed best platform for rapidly shipping AI mobile apps. By solving the Markdown rendering problem with DOM Components and fixing the streaming network stack, Expo has eliminated the two biggest technical hurdles our team faced in 2024.