How do deep links work on Android and iOS?

On Android, App Links associate a web domain with the app through a verification file on the site, so matching links open the app directly. On iOS, Universal Links work the same way using an association file. Both fall back to the website when the app is not installed. Custom URL schemes also work but are less reliable.

How are deep links used in in-app campaigns?

Every button in a nudge, banner, story or popup needs a destination. A deep link sends the user to the exact screen for the action, such as a prefilled payment form or a specific product. Parameters in the link can carry a coupon code, a campaign name or a preselected option.

What is a Deep Link? Definition & Examples

What is a deep link?

Used in a sentence: The offer email should deep link to the cart with the coupon applied, not dump people on the home screen.

How it works

A deep link looks like a normal web address or a custom scheme, with a path that maps to a screen in the app. When a user taps it, the operating system checks whether an installed app has claimed that link. If so, the app opens and its routing code reads the path and parameters, then shows the right screen with the right data.

If the app is not installed, a standard deep link falls back to a web page or the app store. Teams test links on both platforms and both states, installed and not installed, because routing errors are easy to miss and send users to the wrong place.

Example

A food delivery app sends a push notification about a discount on a user’s favourite restaurant. Tapping it opens the restaurant’s menu with the discount already applied, instead of the home screen. Inside the app, a banner for a new feature uses a deep link too, so its button lands on the feature’s settings screen rather than a generic help page.

Deep link vs deferred deep link

	Deep link	Deferred deep link
App installed	Required to open the screen	Not required
What happens otherwise	Falls back to web or store	Survives the install, then opens the screen
Common use	Push, email, in-app buttons	Ads and referral links for new users

A deferred deep link remembers the destination through the install, so a new user lands on the promised content on first open.

Best practices

Keep a single list of supported routes and parameters that marketing and engineering share.
Test every link on Android and iOS, with the app installed and not installed.
Handle logged-out users by sending them to sign in, then on to the destination.
Add campaign parameters so you can attribute what each link drove.

How to do this with Digia Engage

In Digia, calls to action in nudges, widgets and stories route users through deep links, set in the campaign without code. Teams can build and check links with the free deep link generator and deep link tester, then attach them to campaign buttons. Destinations can be changed from the dashboard without an app release. See where links are used on the Nudges product page.

Frequently asked questions

How do deep links work on Android and iOS?: On Android, App Links associate a web domain with the app through a verification file on the site, so matching links open the app directly. On iOS, Universal Links work the same way using an association file. Both fall back to the website when the app is not installed. Custom URL schemes also work but are less reliable.
How are deep links used in in-app campaigns?: Every button in a nudge, banner, story or popup needs a destination. A deep link sends the user to the exact screen for the action, such as a prefilled payment form or a specific product. Parameters in the link can carry a coupon code, a campaign name or a preselected option.