When creating a Dynalink, you can define platform-specific fallback URLs that will be used when the app is not installed on the user’s device. These fields are especially useful in mobile web–to–app transitions in both native and React Native apps.

🧭 Supported parameters:

• android_fallback_url – Used on Android devices when the app is not installed.
• ios_fallback_url – Used on iOS devices when the app is not installed.
• url – Used when the link is opened on a desktop browser.

📦 Example payload:

{
  "android_fallback_url": "https://example.com/android",
  "ios_fallback_url": "https://example.com/ios",
  "url": "https://example.com"
}

Using a Play Store URL as the Android fallback

Fallback URLs are forwarded verbatim. If you point android_fallback_url at a Play Store listing, Dynalinks will not automatically append a referrer parameter, the link’s UTM/referrer settings, or the encoded original URL — that augmentation only happens when Dynalinks builds the Play Store URL itself from a configured Android app on the link.

If you want the install referrer to reach your app via the Google Play Install Referrer API, you have two options:

Option 1 — Recommended: leave android_fallback_url blank

Configure the Android app on the link (android_app with a package_name) and Dynalinks will generate the Play Store URL for you, with the referrer parameter populated from the link’s referrer field (and, if your project has Include link in referrer enabled, a base64-encoded copy of the original click URL as _url).

Option 2 — Include the referrer parameter yourself

If you need a custom Play Store fallback, add the referrer query parameter manually:

https://play.google.com/store/apps/details?id=com.example&referrer=utm_source%3Dnewsletter%26utm_campaign%3Dspring

The referrer value must be URL-encoded. Google preserves it through the install and exposes it to your app via the Install Referrer API.

The same rule applies to ios_fallback_url — if you point it at an App Store URL, Dynalinks does not append Apple Campaign Tracking parameters (pt, ct, mt). Those are only appended when Dynalinks builds the App Store URL itself from a configured iOS app on the link with provider_token and campaign_token set.