Expo Apple External Link

This is a custom Expo Module + Config Plugin which enables an iOS app built with Expo to direct users to an external website for account management and creation.

This custom native module is iOS-only.

[!IMPORTANT] The External Link API requires iOS 16+. You may also need to add expo-build-properties.

External Links

Typically, Apple does not allow apps which contain links to your website on the App Store. Instead, you must implement in-app purchases.

However there is a special exception for "reader" apps. These kinds of apps can optionally apply for an additional Entitlement, and if this is granted then the app will then be allowed on the App Store.

• see https://developer.apple.com/support/reader-apps
• see https://developer.apple.com/documentation/storekit/external_link_account

Module

This Expo Module exposes a single method called openInAppModal(). This calls ExternalLinkAccount.open() in native (Swift) code.

Plugin

The Plugin is responsible for modifying your Entitlements and Info.plist files, using options passed to the plugin in your app.json config.

Usage

Can be included alongside any other Expo Config Plugins in app.json:

"plugins": [
    // ...other plugins...
    [
        "expo-build-properties",
        {
            "ios": {
                "deploymentTarget": "16.0",
            },
        },
    ],
    [
        "expo-apple-external-link",
        {
            "externalLinks": {
                "*": "https://mywebsite.com/subscribe"
            }
        }
    ]
]

The externalLinks Object corresponds to the SKExternalLinkAccount dictionary, and maps country codes to region-specific URLs.

[!TIP] Alternately, the key "*" can be used as a wildcard for all regions.