Create Universal Links for iOS Apps

There are two ways you can setup your app for universal links or any other capability you might want to use in the future. You can use Xcode to create a new app project, could also be generated by the Assistant, and Xcode will create all the necessary definitions for you. The other way is going into the Apple Developer Portal and create a new App Identifier manually and assign the needed capabilities there.

Open your running Mobile Services instance and navigate to the Application Links tab for your app definition under Native/Hybrid - TutorialApp.

In the Application Links tab click on the pencil right next to the Apple Universal Links section to add the Team ID and the Bundle ID.

Fill out the upcoming form:

Click on OK.

The Team ID you should’ve copied from Step 1, if not you can find the id on the Apple Developer Portal.

Mobile Services will ask you to confirm your changes. Always keep in mind that changes on the application links will take up to 10 seconds to be completed. During that time your users are not be able to connect against Mobile Services.

Confirm the dialog to see your application links.

Navigate back to the APIs tab. You should see two QR codes, as well as the generated links:

Leave the page open, you will need the server URL later.

Open your app project in Xcode. In your project’s settings, navigate back to Signing & Capabilities and click the + icon located at the Associated Domains section.

Enter the following domain:

Your link should look something like this - applinks:<YourUser-CFSpace>-com-example-tutorialapp.cfapps.eu10.hana.ondemand.com

Please note the applinks: prefix. It is important you enter it exactly as stated.

If you now build and run the app on your device, you will notice an <app_name>.entitlements file is created, containing the just added capability:

Continue and deploy the app to your physical device and walk through the onboarding process.

Once the app is deployed onto your device, it is now running with the added capability.

The way the universal link work is by the associated domain.

You have defined the application link on Mobile Services. This creates an apple-app-site-association file. This file associates your Mobile Services account domain with your iOS app.

The generated apple-app-site-association file contains a JSON structure with the App ID and URL path which is used as universal link.

Open a browser to https://<YourUser-CFSpace-App>-com-example-tutorialapp.cfapps.eu10.hana.ondemand.com/.well-known/apple-app-site-association and you should see the contents of the file:

The asterisk at the end denotes anything. You can for instance add a product id which could directly open an entity with that product ID.

It is up to the app developer to do something meaningful with the provided context. In the next step, you will simply detect the app is launched via a universal link, and log the URL context to the console.

Open your app’s AppDelegate.swift file, and add the following method right below the closing bracket of the class:

// Universal Link
extension AppDelegate {
    func application(_ application: UIApplication, continue userActivity: NSUserActivity, restorationHandler: @escaping ([Any]?) -> Void) -> Bool {

        logger.info("SAP Mobile Services Universal Link called: ")

        if userActivity.activityType == NSUserActivityTypeBrowsingWeb {
            let url = userActivity.webpageURL!
            logger.info(url.lastPathComponent)
            // Here you can do whatever you want with the URL components
        }
        return true
    }
}

When you click/tap on a universal link, this hook will be called. The userActivity object contains a webpageURL property, which holds the universal link you clicked.

If you provide some context to the universal link URL, it will then be printed to the console by retrieving the lastPathComponent property of the URL.

Build and deploy the app to your physical device. After it has started, you can dismiss it to the background.

The easiest way of testing the universal link is to send it via email or scan the Apple Launch App Code in Mobile Services.

In this example, you simply provide the context start, but it can be anything more meaningful of course.

If you now click on the link or scan the QR code, it should directly open your app without going to Safari first. If you look in the Xcode console, you see it logged the start context it received via the NSUserActivity hook.