---
title: appDir
description: Enable the App Router to use layouts, streaming, and more.
---

> **Good to know**: This option is **no longer** needed as of Next.js 13.4. The App Router is now stable.

The App Router ([`app` directory](/docs/app/building-your-application/routing)) enables support for [layouts](/docs/app/building-your-application/routing/pages-and-layouts), [Server Components](/docs/getting-started/react-essentials#server-components), [streaming](/docs/app/building-your-application/routing/loading-ui-and-streaming), and [colocated data fetching](/docs/app/building-your-application/data-fetching).

Using the `app` directory will automatically enable [React Strict Mode](https://react.dev/reference/react/StrictMode). Learn how to [incrementally adopt `app`](/docs/app/building-your-application/upgrading/app-router-migration#migrating-from-pages-to-app).
