Expo Docs MCP Server

--- title: Preview updates in development builds sidebar_title: Using development builds description: Learn how to use the expo-dev-client library to preview a published EAS Update inside a development build. --- [`expo-dev-client`](/develop/development-builds/introduction/) library allows launching different versions of a project by creating a development build. Any compatible EAS Update can be previewed in a development build. This guide walks through the steps required to load and preview a published update inside a development build using the **Extensions** tab or constructing a specific Update URL. ## Prerequisites - [Create a development build and install it](/develop/development-builds/create-a-build/) on your device or Android Emulator or iOS Simulator. - Make sure your development build has the [`expo-updates` library installed](/eas-update/getting-started/#configure-your-project). ## What is an Extensions tab When using the `expo-updates` library inside a development build, the **Extensions** tab provides the ability to load and preview a published update automatically. ### Preview an update using the Extensions tab Make non-native changes locally in your project and then [publish them using `eas update`](/eas-update/getting-started/#publish-an-update). The update will be published on a branch. After publishing the update, open your development build, go to **Extensions**, and tap **Login** to log in to your Expo account within the development build. This step is required for the **Extensions** tab to load any published updates associated with the project under your Expo account. After logging in, an EAS Update section will appear inside the **Extensions** tab with one or more of the latest published updates. Tap **Open** next to the update you want to preview. In the **Extensions** tab, you can view the list of all published updates for a branch. Tap the branch name in the **Extensions** tab. ## Preview an update using the EAS dashboard You can also preview an update using the EAS dashboard by following the steps below: - Click the published updated link in the CLI after running the command to publish an update. This will open the update's details on the **Updates** page in the EAS dashboard. - Click **Preview**. This will open the **Preview** dialog. - To preview the update, you can either scan the QR code with your device's camera or select a platform to [launch the update under **Open with Orbit**](/review/with-orbit/). ## Construct an update URL As an alternative to the methods described in the previous sections, you can construct a specific URL to open your EAS Update in the development build. The URL will look like the following: Let's break this URL to understand what each part does: | Part of URL | Description | | --------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------- | | `slug` | The project's [slug](/versions/latest/config/app/#slug) found in the app config. | | `://expo-development-client/` | Necessary for the deep link to work with the [`expo-dev-client`](/versions/latest/sdk/dev-client/) library. | | `?url=` | Defines a `url` query parameter. | | `https://u.expo.dev/675cb1f0-fa3c-11e8-ac99-6374d9643cb2` | This is the updates URL, which is inside the project's app config under [`updates.url`](/versions/latest/config/app/#url). | | `/group/47839bf2-9e01-467b-9378-4a978604ab11` | The group ID of the update. | Once you've constructed the URL, copy and paste it directly into the development build's launcher screen under **Enter URL Manually**. Alternatively, you can [create a QR code for the URL](/more/qr-codes/) and scan it using your device's camera. When scanned, the URL will open up the development build to the specified channel. ## Example <BoxLink title="See a working example" description={ <> See a working example of using expo-dev-client with EAS Update. </> } Icon={GithubIcon} href="https://github.com/jonsamp/test-expo-dev-client-eas-update" />