Contents

Confirming a person’s physical location

Add code to quickly confirm a person’s physical location while respecting their privacy.

Overview

If you create an App Clip that people invoke at a physical location, you may need to confirm a person’s location before allowing them to perform a task. For a quick launch and to preserve user privacy, App Clips use a lightweight mechanism in which the system verifies that a person is at a specific, expected location. When you adopt this mechanism, and when people allow it, the App Clip card contains a note that tells people that the App Clip can verify their location. They can disable location verification by tapping the note on the App Clip card.

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Enable your App Clip to verify a person’s location

To enable your App Clip to verify the person’s location, modify your App Clip’s Info.plist file:

  1. Open your App Clip’s Info.plist, add the NSAppClip key, and set its type to Dictionary.

  2. Add an entry to the dictionary with NSAppClipRequestLocationConfirmation as the key, select Boolean as its type, and set its value to true.

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Alternatively, open the Info.plist file in the property list editor and add the entry by selecting App Clip from the list of keys. This adds the NSAppClip key and the following entries of type Boolean to its dictionary: “Requests ephemeral user notifications” and “Requests location confirmation.” Per default, the value for both entries is NO. Change the value for “Requests location confirmation” to YES.

Add code that verifies the physical location

After you modify your App Clip’s Info.plist file, add code to provide the expected physical location information to the App Clip. To retrieve this information, encode an identifier in the URL that launches the App Clip, and use the identifier to look up the location information for a business in your database. Alternatively, encode the location information in the URL that launches the App Clip.

On launch, access the location information, use it to create a CLCircularRegion object with a radius of up to 500 meters, and pass it to the confirmAcquired(in:completionHandler:) function.

The following code verifies a person’s location when they launch the App Clip. Make sure to update your user interface for each possible result, including the case where a person denies access to location services on their device.

import UIKit
import AppClip
import CoreLocation

class SceneDelegate: UIResponder, UIWindowSceneDelegate {
    
    var window: UIWindow?
    
    // Call the verifyUserLocation(_:) function in all applicable lifecycle callbacks.

    func verifyUserLocation(_ activity: NSUserActivity?) {
        
        // Guard against faulty data.
        guard activity != nil else { return }
        guard activity!.activityType == NSUserActivityTypeBrowsingWeb else { return }
        guard let payload = activity!.appClipActivationPayload else { return }
        guard let incomingURL = activity?.webpageURL else { return }

        // Create a CLRegion object.
        guard let region = location(from: incomingURL) else {
            // Respond to parsing errors here.
            return
        }
        
        // Verify that the invocation happened at the expected location.
        payload.confirmAcquired(in: region) { (inRegion, error) in
            guard let confirmationError = error as? APActivationPayloadError else {
                if inRegion {
                    // The location of the NFC tag matches a person's location.
                } else {
                    // The location of the NFC tag doesn't match the records,
                    // for example, if someone moved the NFC tag.
                }
                return
            }
            
            if confirmationError.code == .doesNotMatch {
                // The scanned URL isn't registered for the App Clip.
            } else {
                // A person denied location access, or the source of the
                // App Clip’s invocation isn't an NFC tag or visual code.
            }
        }
    }

    func location(from url:URL) -> CLRegion? {
        let coordinates = CLLocationCoordinate2D(latitude: 37.334722,
                                                 longitude: 122.008889)
        return CLCircularRegion(center: coordinates,
                                radius: 100,
                                identifier: "Apple Park")
    }
}

For more information on how you can access the App Clip’s invocation URL, refer to Responding to invocations.

See Also

Launch