App deep linking that opens your app
Connect your iOS and Android app to a domain, and every link opens the app when it's installed — and sends everyone else to the right app store. A Firebase Dynamic Links alternative, with no SDK required to start.
What is app deep linking?
App deep linking is a link that opens a specific screen inside a mobile app instead of a web page. When you connect your app to a domain, a normal https link on that domain opens your app directly — through iOS Universal Links and Android App Links, the OS-level standards Apple and Google verify. If the app isn't installed, the same link sends the visitor to the app store or your website, so one link works for everyone.
This is for your own app. Opening popular apps like YouTube or Instagram from a link is a separate feature — see the deep link generator.
One link, every visitor routed right
Set it up once, and the link decides where each person should go.
App installed
The operating system opens your app directly to the right screen — via iOS Universal Links and Android App Links. Instant, no interstitial.
iPhone without the app
Sent to your App Store page so they can install, instead of a dead-end web view.
Android without the app
Sent to your Play Store page, with the original link carried in the install referrer so your app can restore context after install.
Desktop
Falls back to your web page — the same link works everywhere, for everyone.
How to set it up
U2L handles the verification files; your app declares the domain. No servers, no cert wrangling.
- 1
Connect your app to a domain
Add your iOS Team ID + Bundle ID and Android package name + signing fingerprint under App Links in the dashboard, on a verified custom domain or subdomain.
- 2
We serve the association files
U2L automatically publishes the /.well-known/apple-app-site-association and assetlinks.json files Apple and Google verify — no hosting or config on your side.
- 3
Your app declares the domain
Add the domain to your app's Associated Domains (iOS) and an autoVerify intent filter (Android). Your app resolves the link's slug via the API.
- 4
Create app links
Every link on that domain now opens your app when installed and routes to the store or web when it isn't — automatically.
Full setup guide with code snippets: developers/app-deep-links
A Firebase Dynamic Links alternative
Google shut down Firebase Dynamic Links in August 2025, leaving teams without a simple way to open their app from a link and route to the store when it isn't installed. U2L covers that core behavior: connect your app to a domain, and your links open the app via verified Universal Links and App Links, fall back to the store, and carry install-referrer context on Android. See the migration guide for a full comparison.
App deep linking FAQ
What is app deep linking?+
App deep linking is a link that opens a specific screen inside a mobile app when the app is installed, instead of a web page. With U2L, links on your connected domain open your app via iOS Universal Links and Android App Links, and fall back to the app store or your website when the app isn't installed.
How do links open my app without a custom scheme?+
Through the official mechanisms — iOS Universal Links and Android App Links. Your app declares that it handles your domain, and the OS verifies ownership by fetching the association files U2L serves for that domain. A tapped https link then opens your app directly.
What happens if the app isn't installed?+
Mobile visitors without the app go to the right store — the App Store on iPhone, Google Play on Android — and desktop visitors go to your web page. You set this up once; every app link routes automatically.
Is this a Firebase Dynamic Links alternative?+
Yes. Google shut Firebase Dynamic Links down in August 2025, and U2L covers the core replacement: your links open your app when installed and route to the store when it isn't. See our migration guide on the blog for how the pieces map over.
Do I need to install an SDK?+
No SDK is required to get started. U2L serves the association files and the app-open behavior works through the OS. Your app reads the link on open and resolves it via our API. (Full deferred deep linking on iOS — restoring the exact screen after a fresh install — does require app-side handling.)
What is deferred deep linking?+
It's carrying a visitor to the right in-app screen even when they had to install the app first. On Android, U2L passes the original link in the Play Store install referrer so your app can restore context after install. On iOS, the store opens without link context unless you add your own attribution SDK.
Can I use a subdomain instead of a custom domain?+
Yes. App links work on a verified custom domain or a U2L subdomain. Apple and Google verify app ownership per domain, so use a dedicated domain or subdomain for your app links.
Does my app open to the exact screen, or just the home screen?+
Your app receives the full link, so it can route to any screen. The link carries the path and slug; your app resolves it (via our API or your own mapping) and navigates the user to the right place.
How is this different from opening popular apps like YouTube or Instagram?+
That's a separate feature — the deep link / app opener for well-known third-party apps. App deep linking here is for your own app: you connect it to a domain and the OS opens it via verified universal/app links.
Does it work for both iOS and Android?+
Yes. Configure iOS (Team ID + Bundle ID) and Android (package name + SHA-256 fingerprint) independently — enable one or both. U2L serves the matching association file for each platform you set up.
Open your app from every link
Connect your iOS and Android app to a domain and turn your links into app openers — with automatic store fallback.