continuous iOS location updates in background - ios

Question

I am trying to create a simple iOS app that will continuously track location in the background and notify with high accuracy when the user has entered a specific region (don't want to use region monitoring because it's not accurate or fast enough for what I want).
This app works fine in the foreground but once I go into the background it does not work.
I created a test app to investigate how background location updates work. I made a simple app that just prints out a message when a location update happens (to the log).
What I see is that in foreground mode the updates happen as expected but when I lock my phone and the app switches to background the location updates happen for about 30 seconds and then stop. There is no mention in the Apple docs (that I can find) explaining this behavior.
I made sure that I enabled background processing in the info.plist (done in "capabilities" --> "background modes" --> "location updates")
Here is the code I used to test this:
import UIKit
import CoreLocation
class ViewController: UIViewController, CLLocationManagerDelegate {
let locationManager = CLLocationManager()
var counter = 0
override func viewDidLoad() {
super.viewDidLoad()
// configure location updates
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.distanceFilter = 0.1
locationManager.pausesLocationUpdatesAutomatically = false
locationManager.requestAlwaysAuthorization()
locationManager.startUpdatingLocation()
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
print("location updated! \(counter)")
counter = counter + 1
}
Any ideas on what I might be missing? I tried different location accuracy settings (such as BestForNavigation, etc) and no change.
Thanks.

Answer 1

You have to add this in your plist :
<key>UIBackgroundModes</key>
<array>
<string>location</string>
</array>
add this
locationManager.allowsBackgroundLocationUpdates = true

Answer 2

I think this might be the answer:
allowsBackgroundLocationUpdates.
Apps that want to receive location updates when suspended must include
the UIBackgroundModes key (with the location value) in their app’s
Info.plist file and set the value of this property to true.
...
The
default value of this property is false.
Are you setting that?

Answer 3

You can add these two line to make it working in background mode:
locationManager!.allowsBackgroundLocationUpdates = true
locationManager!.pausesLocationUpdatesAutomatically = false