Most marketers have at some point submitted a brief to engineering that says "create a deep link" and received a working link days later with no real understanding of what was actually built. The link either works or it doesn't. When it doesn't, the campaign goes live anyway, users land somewhere wrong, and spend compounds behind a broken user experience.
This gap between marketing intent and engineering output is not a skills problem. It's a communication problem caused by the fact that deep linking has historically been documented for developers, not for the people who decide when and where links are used in campaigns.
This guide flips that. No code snippets, no SDK documentation, no Apple developer portal tutorials. Just the parts marketing teams need to know to brief engineering correctly, test links before launches, and understand why link configuration directly affects conversion rates.

What Deep Links Actually Do for Your Campaigns

A deep link routes a user to a specific screen inside an app rather than to the app's home screen or a generic webpage. The distinction sounds minor. The impact on campaign performance is not.
When a user taps a paid ad for a specific product, every extra step between the ad and the product is a conversion loss. Research across consumer apps consistently shows that 40-60% of users who land on a home screen after clicking a specific product ad do not complete the intended action. That friction is built into every campaign that uses the wrong link type, and most marketers don't know it's happening.
Deep links carry destination parameters inside the URL. When a user taps the link, the app receives an instruction to open a specific screen directly. A campaign ad for a flash sale on footwear takes the user to the sale page, not the homepage. The conversion rate improvement from proper deep link routing is measurable and substantial, particularly for new user acquisition campaigns.

The 4 Types of Deep Links Marketers Should Know

Standard deep links use custom URI schemes (like myapp://product/123). They work when the user already has the app installed and break when the app is not installed. These are appropriate for re-engagement campaigns targeting your existing user base, not for acquisition.
Universal Links (iOS) and App Links (Android) are HTTPS-based links that the operating system routes directly to the app. They're more reliable than custom URI schemes, degrade gracefully when the app isn't installed by falling through to a web page, and are the preferred format for most paid acquisition campaigns.
Deferred deep links are the most important type for new user acquisition. When a user who doesn't have the app taps the link, the destination is stored. They get redirected to the app store, install the app, and on first open the app retrieves the stored destination and routes them to the correct screen. Without deferred deep linking, every new user from a paid campaign lands on the home screen by default. The mechanics and conversion impact of this are covered in detail in the guide to how deferred deep linking preserves context through install.
Dynamic deep links are links created through a platform that manages routing, fallback behaviour, and attribution parameters automatically. Rather than hardcoding destinations into URLs, routing rules are configured in a dashboard and resolved at the time of click. Most growth teams use dynamic links in practice because they can be updated without changing the URL and work reliably across platforms.

What to Include in Your Deep Link Brief to Engineering

The most common reason campaigns launch with broken links is an incomplete brief. Engineering teams build what they're asked to build. When the brief doesn't specify fallback behaviour or attribution parameters, those elements get omitted.
A complete deep link brief should include five things:
1. Destination screen. Which specific in-app screen should the user land on? Not "the product page" but the exact screen identifier. Engineering needs a specific route, not a description. Get the correct screen path from your product team before writing the brief.
2. Fallback destination. What happens if the user doesn't have the app, or if the link fails to open the app in some in-app browser environments? Options include a web version of the product page, the app store listing, or a custom landing page. This must be specified, not assumed.
3. New vs returning user behaviour. Should a new user who installs via the link go directly to the promoted screen, or complete onboarding first? This is a product decision that marketing should specify. Left unspecified, engineering will make a default choice that may not reflect campaign intent.
4. Attribution parameters. Which campaign, channel, and creative does this link belong to? Parameters like utm_campaign, utm_source, and utm_medium must be appended, or attribution reporting will be incomplete. Your daily and weekly KPI tracking will only be reliable if attribution parameters are correctly configured from the start.
5. Expiry. Does this link have an end date? A flash sale link that continues routing users to an out-of-stock page after the sale ends creates a worse experience than no link at all. Specify expiry dates and define what happens when the link expires.

How to Test Links Before Launching Spend

Sending budget behind an untested link is one of the most avoidable mistakes in performance marketing. Testing deep links doesn't require engineering skills, but it does require a structured process and real devices.
Test the installed-user flow. Open the link on a device with the app installed. Does it route to the correct screen? Copy the exact URL from your ad creative and test it on a real device, not a simulator.
Test the new-user flow. Uninstall the app from a test device. Click the link. You should be taken to the app store. Install and open the app. Does it route to the correct destination? This is the deferred deep link test, and it's the one most teams skip. It is the most critical test for any acquisition campaign.
Test from the actual channel. If the ad will run on Instagram, click the test link inside Instagram's in-app browser on both iOS and Android. Instagram, Facebook, Gmail, and WhatsApp all use custom webviews that handle deep links differently from Safari and Chrome. A link that works in a standard browser can fail silently inside these environments.
Verify attribution. After completing the test install, check your MMP dashboard. Is the install attributed to the correct campaign and channel? If attribution parameters aren't showing up, the campaign will generate unattributed installs that cannot be optimised.
These four tests take under 30 minutes and catch the majority of link failures before spend is committed.

Measuring Deep Link Impact on Conversion Rates

Most teams know that deep links improve conversion rates, but few measure the improvement systematically. Here is how to quantify it.
Compare install-to-first-action rates by link type. If some campaigns use deferred deep links and others fall back to a home screen, the conversion difference shows up in D0 and D7 event data. A user routed to the promoted product is measurably more likely to convert than one who must find it manually.
Track destination match rate as a metric. Ask engineering to fire an event when a user successfully reaches the deep link destination (as opposed to the fallback screen). The ratio of this event to total installs from deep link campaigns is your deferred match rate. Aim for above 85% on Android and above 65% on iOS post-ATT.
Segment ROAS by link configuration. If you're running campaigns with different link types or fallback configurations, compare ROAS across segments. Better routing typically produces higher D0 and D7 ROAS because intent is preserved from click to first session.
Audit unattributed installs. A growing organic bucket in your attribution dashboard that correlates with paid campaign activity often indicates missing attribution parameters. This masks your true campaign ROAS and makes budget allocation decisions unreliable.

Common Mistakes That Waste Ad Spend

Using standard links for acquisition campaigns. Standard deep links break when the app isn't installed. Any campaign targeting new users must use deferred deep links. This is the single most common and most costly deep link mistake in consumer app marketing.
Not configuring fallbacks. In certain in-app browser environments on iOS, deep links fail silently and users land on a blank page or encounter an error. Without a configured fallback, you're losing users at an invisible failure point with no signal in the data.
Testing from the wrong environment. Testing a link in Safari and then deploying it in a Facebook campaign is a persistent source of broken links that teams discover only after spend goes live. The test environment must match the deployment environment.
Missing attribution parameters. A link without attribution parameters produces unattributed installs. These can't be attributed to campaigns, can't be optimised, and inflate your apparent organic channel. This is a persistent reporting problem in apps that build campaign links manually rather than through a link management platform.
Using static links for evolving campaigns. If a promoted product goes out of stock or a campaign creative changes, static links continue pointing to the old destination. Dynamic links allow destination updates without changing the URL, preventing this category of failure entirely.

Deep Link Requests That Engineering Will Thank You For

Provide specific destination identifiers, not descriptions. "The summer sale product page" requires interpretation. "Product ID 4892 at /app/products/4892" does not. Getting the exact identifier from your product team takes five minutes and prevents a round of clarification after the link is built.
Specify platform requirements upfront. iOS and Android occasionally require different routing logic, particularly for in-app browser fallbacks and Universal Link vs App Link handling. If the brief doesn't address both platforms, one will often be under-specified.
Include a testing plan in the brief. Describe the exact tests you'll run to sign off. This defines acceptance criteria upfront and reduces post-delivery revision cycles significantly.
Maintain a link inventory. A simple internal log of live links, their campaigns, and expiry dates prevents campaigns from running on stale links and gives engineering clarity on which links are safe to deprecate.
The most effective teams treat the deep link brief as a shared contract: marketing defines what success looks like, engineering builds to that specification, and QA confirms it before spend goes live. For teams that want to reduce dependency on engineering tickets for standard campaign links, platforms like Linkrunner let marketers create and preview dynamic deep links directly, with built-in routing previews and link-level analytics showing whether users are reaching the intended destination. Request a demo to see how this works with your current campaign setup.

Frequently Asked Questions

What's the difference between a deep link and a tracking link?
A tracking link records attribution data (which campaign, channel, and creative drove the user). A deep link routes the user to a specific in-app destination. Most modern campaign links combine both: they track the attribution and route the user to the correct screen. Using one without the other means either poor attribution data or incorrect routing.
Do deep links work from email campaigns?
Yes, but email clients behave differently from web browsers. Gmail on iOS handles Universal Links inconsistently. Apple Mail handles them well. Always test deep links from the specific email client your audience is most likely to use before deploying to a campaign.
What happens if a deep link points to a screen that no longer exists?
The user typically lands on a 404 state or the app home screen, with no error shown to you. Dynamic links mitigate this by allowing destination updates without changing the URL. Static links require issuing a new URL or implementing a server-level redirect.
Do deep links work for every paid ad network?
Yes, but with format-specific differences. Meta, Google, TikTok, and Apple Search Ads all support deep linking in ads. Certain formats like Meta Instant Experiences have additional requirements. Always verify the specific ad format documentation before assuming a standard link will work.
How long should deep link setup take for a new campaign?
With a dynamic link platform, creating the link itself takes minutes. The testing process, particularly the deferred install flow and in-app browser testing, takes 1-2 hours on real devices. Budget at least one full testing day before any campaign go-live date.