What is deferred deep linking? How it works on Android and iOS, without Firebase

How does deferred deep linking work?

1. Tap: a user without your app taps a link, for example https://example.com/invite/abc123.
2. Save the destination: the link goes to your server or a deep linking service first, which saves where the user was going (invite=abc123).
3. Send to the store: the user is redirected to your Google Play or App Store listing and installs.
4. Match on first open: the app starts and asks "did this user come from a link?" This is the hard step, and it works differently on each platform.
5. Open the screen: the app reads the destination and shows the invite.

How do I do deferred deep linking on Android?

Android has a free, reliable way to do step 4: the Google Play Install Referrer API.

1. Put your destination in the referrer parameter of your Play Store link, URL-encoded: https://play.google.com/store/apps/details?id=com.example.app&referrer=invite%3Dabc123
2. Add the com.android.installreferrer:installreferrer library to your app.
3. On first open, read the referrer:

val client = InstallReferrerClient.newBuilder(context).build()
client.startConnection(object : InstallReferrerStateListener {
    override fun onInstallReferrerSetupFinished(responseCode: Int) {
        if (responseCode == InstallReferrerClient.InstallReferrerResponse.OK) {
            val referrer = client.installReferrer.installReferrer // "invite=abc123"
            openFromReferrer(referrer)
        }
        client.endConnection()
    }
    override fun onInstallReferrerServiceDisconnected() {}
})

4. Save a flag so you only handle it once. The referrer stays the same for that install, so without the flag you'd open the invite on every launch.

This works only for installs from Google Play. Your web link can decide where to send people: open the app with an App Link if it's installed, otherwise redirect to the Play Store URL with the referrer attached.

How do I do deferred deep linking on iOS?

The App Store doesn't pass any data from the link to your app after an install, so there's no iOS equivalent of the Install Referrer. Your options:

• A deep linking service. Branch, AppsFlyer OneLink, Adjust and Airbridge match the install to the earlier click for you. Check what data they collect, because you must declare it in your App Store privacy labels, and Apple doesn't allow fingerprinting devices to track users.
• The clipboard. A web page copies the destination to the clipboard and the app reads it on first open. Since iOS 16 that shows a "paste" permission prompt, so it's clunky and many users decline.
• Accounts or codes. If users sign in, store the pending invite against their email or account on your server, and fetch it after sign-in. Or show a short invite code the user types in. Low-tech, but private and reliable.
• A sensible default. Open the screen most new users come for, or ask "What brought you here?" on the first screen.

What replaced Firebase Dynamic Links?

Firebase Dynamic Links shut down in August 2025, and its links stopped working. There's no direct free replacement from Google. Most apps moved to:

• Universal Links and App Links for normal deep links (free, built into the platforms).
• The Install Referrer API for deferred deep links on Android (free).
• A paid or free-tier deep linking service when they need deferred deep links and attribution on both platforms.

If your app still has old page.link URLs in emails, docs or QR codes, replace them: they no longer open your app.

Do I actually need deferred deep links?

Only if new users arrive through links that point at something specific. You probably need them for:

• Invites and referrals ("join my team", "play with me").
• Shared content (a recipe, a playlist, a listing) that new users should land on.
• Paid campaigns that promise one specific thing.

You probably don't for a launch link, a website "Download" button or most social posts: those just need the store listing. For a launch, a clean store listing does more than any link trick.

Next steps

Set up normal deep links first, then add the Install Referrer on Android, and pick an iOS option based on how much invites matter to you. Test the full path on a phone that doesn't have the app: tap, install, first open. When it works, list your app on TrueLaunch for free so new users can find it in the first place.