Deep Link Definition: Types and Mobile App Examples

A deep link is a URL that opens a specific page or screen inside a mobile app or website, rather than the home page or app launch screen. It lets marketers send users straight to a product, article, or in-app feature with a single tap. The term is most commonly used in the context of mobile apps, but the concept applies to any URL that targets a specific resource beyond the home page.

Why Deep Links Matter

Deep links remove friction between a click and a conversion. Without them, a tap on an ad or email link drops the user on the app’s home screen, forcing them to navigate to the page they actually wanted. Studies from Branch and Adjust have shown that deep-linked campaigns produce noticeably higher in-app conversion rates and shorter session times to action than home-screen drops.

Deep links also fix attribution. They preserve the campaign source through the app open, so a click on a Facebook ad correctly registers as a Facebook-driven install or session. Without deep links, mobile attribution often loses the source between web click and app launch.

The trade-off is engineering work. Each platform (iOS, Android, web) has its own deep link standard, and developers must register URL schemes or association files for the links to resolve correctly.

Types of Deep Links

Three deep link types exist. Choose based on whether the app is already installed and whether mobile attribution is required.

Standard deep links open a specific in-app screen, but only if the app is already installed. If the app is missing, the link fails or drops to a blank page. Standard deep links use a custom URI scheme such as myapp://product/12345.
Deferred deep links route users to the right in-app screen even when the app is not installed. The link first sends them to the App Store or Play Store, then opens the target screen after install. This is the type most mobile marketing campaigns need.
Universal Links (iOS) and App Links (Android) are HTTPS URLs that open the app if installed and fall back to the website if not. Apple released Universal Links in iOS 9 (September 2015). Google released App Links in Android 6.0 Marshmallow (October 2015). These are the modern default and replace older custom URI schemes.

How Deep Links Work

Deep links rely on a registered association between a URL and a specific app. The mobile operating system reads the URL when a user taps it and routes the request based on the registration.

Three example formats:

URI scheme: myapp://product/12345
Universal Link: https://example.com/product/12345
App Link: https://example.com/product/12345

Universal Links and App Links use the same HTTPS URL format that the website uses. The operating system distinguishes between web and app behavior using an association file:

iOS: Apple’s apple-app-site-association JSON file hosted at https://example.com/.well-known/apple-app-site-association
Android: Google’s assetlinks.json file hosted at https://example.com/.well-known/assetlinks.json

Mobile attribution platforms such as Branch, AppsFlyer OneLink, and Adjust wrap these standards with deferred deep linking, install attribution, and analytics on top.

Deep Link vs Universal Link vs App Link

Aspect	URI Scheme Deep Link	Universal Link (iOS)	App Link (Android)
URL format	`myapp://path`	`https://example.com/path`	`https://example.com/path`
Works without app installed	No	Yes (falls back to web)	Yes (falls back to web)
Required setup file	URL scheme registration	`apple-app-site-association`	`assetlinks.json`
OS support	All iOS and Android	iOS 9 and later	Android 6.0 and later
Recommended for new builds	No	Yes	Yes

URI scheme deep links still work but are considered legacy. Apple and Google both recommend Universal Links and App Links for any new app development.

How to Create a Deep Link With Tracking

Adding UTM parameters to a deep link is the standard way to track campaign attribution in mobile app installs and sessions. The format works the same as a regular UTM-tagged URL.

https://app.example.com/product/12345?utm_source=facebook&utm_medium=paid_social&utm_campaign=spring_sale

The mobile attribution platform parses these parameters during the install or open event and forwards them to the analytics destination, typically Google Analytics 4 (GA4) or Firebase. Use linkutm’s UTM builder to construct correctly formatted UTM parameters for any deep link.

Two practical tips:

Keep parameter values lowercase and consistent. Mobile attribution joins web and app sessions on these values. Capitalization mismatches break the join.
Test the deep link on both platforms before launch. A common bug is iOS opening the App Store while Android opens the app correctly, due to a missing entry in the association file.

Common Deep Link Issues

Three problems appear in most mobile campaigns.

The link does not open the app. This usually means the association file is missing, malformed, or not served over HTTPS with a valid certificate. Apple’s apple-app-site-association must be served without a . json extension and with Content-Type: application/json.

The deep link works on one platform but not the other. iOS and Android use different association files and entitlements. A working iOS Universal Link does not automatically mean Android App Links are configured. Both must be set up and tested separately.

Deep links break inside in-app browsers. Facebook, Instagram, and X (Twitter) often open links inside their own browser, which can intercept Universal Links. Use a deferred deep link or a pre-flight redirect to push the user out to the system browser before the link is resolved.

Frequently Asked Questions

What is a deep link in simple terms?

A deep link is a URL that opens a specific page or screen, not the home page. On mobile, it opens a particular screen inside an app, such as a product detail page or a saved-items list. On the web, it points to a specific URL deeper than the home page.

What is a deep link example?

A deep link example for a mobile e-commerce app might be https://shop.example.com/product/12345, which opens the product detail screen for item 12345 inside the app. The same URL falls back to the corresponding web page if the app is not installed.

What is the difference between a deep link and a deferred deep link?

A standard deep link only works if the app is already installed; if it is not, the link fails. A deferred deep link sends the user through the App Store or Play Store, waits for install, and then opens the original target screen on first launch. Deferred deep links are the standard for mobile marketing campaigns.

Are Firebase Dynamic Links still available?

No, Google announced the deprecation of Firebase Dynamic Links in 2024, with full shutdown in 2025. Teams using Firebase Dynamic Links need to migrate to alternatives such as Branch, AppsFlyer OneLink, Adjust, or build native Universal Links and App Links.

Do deep links work with UTM parameters?

Yes, deep links can carry UTM parameters just like any other URL. Mobile attribution platforms read the parameters on app open and forward them to analytics tools such as GA4. This is how campaign source data survives the install process and shows up correctly in attribution reports.

To add UTM tracking to a mobile deep link before launch, build the parameters with the free UTM builder and test the resulting URL on both iOS and Android.