What is Deep Linking?
Also known as: App deep link, Universal link, App Link
What is deep linking?
Deep linking is a URL that opens a specific destination inside a mobile app or a specific page on the web, rather than the homepage. On mobile, the destination is a screen inside the app. On the web, it is a URL fragment or path that scrolls or navigates to a section of a page.
The point is the same in both cases. Send the user exactly where the click promised.
A non-deep-linked ad for a pair of running shoes drops the user on the retailer's homepage. A deep-linked ad drops the user on the product page for that exact shoe, with size and color preselected. The difference shows up immediately in conversion rate.
Types of deep links
There are five common types. Each solves a different routing problem.
Regular deep links
A regular deep link works only when the app is already installed. Click it and the OS opens the app to the target screen. Click it without the app installed and the link breaks. Useful for re-engagement campaigns aimed at existing users.
Deferred deep links
A deferred deep link survives the install. The user clicks an ad, gets routed to the App Store, installs the app, opens it for the first time, and lands on the exact screen the ad pointed to. Mobile measurement partners (MMPs) like Branch and AppsFlyer pioneered the pattern.
Contextual deep links
A contextual deep link carries data with it. Campaign ID, referrer, promo code, product SKU. The app reads the parameters on launch and personalizes the first screen. A coupon code prefilled at checkout is a contextual deep link in action.
Universal Links (iOS)
Universal Links are Apple's standard, introduced in iOS 9. The OS verifies the domain via an apple-app-site-association file, then routes matching https:// URLs to the app automatically. No protocol handler. No chooser dialog. Source: Apple Developer documentation.
App Links (Android)
App Links are Google's equivalent on Android, introduced in Android 6.0. Domain ownership is verified via an assetlinks.json file in /.well-known/. Verified App Links open the app directly without the disambiguation dialog. Source: Android Developers documentation.
| Type | Works without app installed | Carries parameters | Requires domain verification |
|---|---|---|---|
| Regular deep link | No | Limited | No |
| Deferred deep link | Yes | Yes | Recommended |
| Contextual deep link | Depends | Yes | Recommended |
| Universal Links (iOS) | Falls back to web | Yes | Yes |
| App Links (Android) | Falls back to web | Yes | Yes |
How deep linking improves ad campaigns
Three concrete payoffs from deep linking paid traffic into apps and product pages.
Attribution survives the install. Without a deferred deep link, a paid install opens to the home screen and the campaign context is lost. The MMP can still credit the install, but the in-app journey starts from zero. Deferred deep links carry campaign ID, ad set, and creative ID into the first session.
Friction drops. Every extra tap between ad click and the action you want costs roughly 20 to 30 percent of the audience. A deep link removes the homepage, the search step, and the category filter in one move.
Conversion rates climb. Branch's published benchmark data puts deep-linked campaigns at 2x to 4x the conversion rate of non-deep-linked campaigns of the same audience and creative. Source: Branch Mobile Growth Handbook 2024.
This is why every serious mobile advertiser routes paid traffic through a deep link, not a raw store URL.
Universal Links vs App Links vs custom URI schemes
Three competing mechanisms exist. Only two are recommended in 2026.
| Mechanism | Platform | Domain verified | Chooser dialog | Recommended |
|---|---|---|---|---|
| Universal Links | iOS 9+ | Yes (AASA file) | No | Yes |
| App Links | Android 6+ | Yes (assetlinks.json) | No (if verified) | Yes |
| Custom URI schemes | Both | No | Yes | No |
Custom URI schemes (myapp://product/123) were the original deep linking mechanism. They still work, but any app can claim any scheme, the OS shows a chooser dialog, and the link breaks if the app is not installed. Apple and Google both deprecated the pattern in favor of verified domain links. Use custom schemes only as a fallback inside a wrapper from an MMP.
Tools for deep linking
Most teams do not roll their own. The cost is a per-link fee or an MMP subscription. The benefit is one URL that resolves correctly across iOS, Android, web fallback, App Store, and Play Store.
- Branch. The most widely used deep linking platform. Free tier covers up to 10K monthly active users. Strong attribution, deferred deep linking, and SKAN postback support.
- AppsFlyer OneLink. Bundled with the AppsFlyer MMP. Single URL routes to iOS, Android, web, or store. Tight integration with their attribution dashboard.
- Adjust. MMP-first. Their deep linking sits inside the Adjust tracker URL. Good fit for teams already on Adjust.
- Firebase Dynamic Links. Sunset on August 25, 2025. No longer an option for new projects. Existing implementations stopped resolving on that date. Source: Firebase support.
For most performance teams, Branch or AppsFlyer OneLink is the default. Adjust if attribution is already living there. Never start a new project on Firebase Dynamic Links.
Real-world example with numbers
A direct-to-consumer footwear app runs a Meta Advantage+ Shopping campaign. Spend: $80,000 over 30 days. Two ad sets, identical creative, identical targeting.
- Ad set A. Click destination is the App Store URL. New users land on the home screen after install.
- Ad set B. Click destination is a Branch deferred deep link. New users land on the exact product page after install, with size preselected based on the ad creative.
Results after 30 days:
- Install-to-purchase rate, set A: 4.1 percent.
- Install-to-purchase rate, set B: 11.7 percent.
- 7-day retention, set A: 18 percent. Set B: 28 percent.
- Cost per purchase, set A: $42. Set B: $15.
Same audience, same creative, same budget. The deferred deep link did the work. The product team paired the deep link with conversion tracking on the post-install purchase event so the mobile attribution chain stayed intact.
Deep linking in 2026
Three shifts changed the landscape this year.
Firebase Dynamic Links is gone. The August 2025 sunset forced an industry-wide migration. Branch and AppsFlyer captured most of the displaced traffic.
Privacy frameworks changed the postback flow. iOS 14.5 ATT and SKAdNetwork (SKAN) reshaped what attribution data flows back to the network. Deep links still route the user, but the campaign-level conversion signal now arrives via SKAN postbacks rather than IDFA-based pings.
Web-to-app deep linking is back in focus. Apple's App Clips and Google's Instant Apps never broke through. Universal Links and App Links did. Brands now invest more in their mobile web experience because every paid click that hits the site is one Universal Link tap from being inside the app.
The rule is simple in 2026. If you run paid traffic to a product available in an app, route it through a verified deep link. If you do not, you are paying full CPM and capturing a fraction of the conversion.
Related terms
Frequently asked questions
What is the difference between a deep link and a regular URL?
A regular URL opens a website in a browser. A deep link routes the user into a specific in-app screen if the app is installed, or falls back to the web or App Store if it is not. Mobile deep links carry parameters that survive the install, so attribution and context follow the user.
Are Universal Links and App Links the same thing?
No. Universal Links are Apple's iOS standard. App Links are Google's Android standard. Both verify ownership of a domain so the OS can open the app directly without a chooser dialog. The mechanics differ. The intent is the same. A cross-platform tool like Branch or AppsFlyer OneLink wraps both behind one URL.
What is a deferred deep link?
A deferred deep link routes a user who does not yet have the app installed. They click the ad, install from the store, open the app for the first time, and land on the exact screen the ad pointed to. Without deferred deep linking, every new install opens to the generic home screen and the campaign context is lost.
Does Firebase Dynamic Links still work?
No. Google fully shut down Firebase Dynamic Links on August 25, 2025. Existing links stopped resolving. Teams that relied on FDL had to migrate to Branch, AppsFlyer OneLink, Adjust, or roll their own Universal Links plus App Links setup. Source: Firebase support announcement.
Do deep links improve ad performance?
Yes. Branch's 2024 Mobile Growth Handbook reports that campaigns using deep links convert at 2x to 4x the rate of non-deep-linked campaigns, with a 40 percent lift in 7-day retention. Removing the homepage detour is the single biggest reason.