I took apart apple's example to only show relevant information on how to get the device's current GPS coordinates

PotlocViewControllerModified.swift

/*
Copyright (C) 2016 Apple Inc. All Rights Reserved.
See LICENSE.txt for this sample’s licensing information

Abstract:
Contains the PotlocViewController which shows how to use CLLocationManager and WCSession together to communicate between an iPhone and an Apple Watch.
*/

import UIKit
import CoreLocation


class PotlocViewController: UIViewController, CLLocationManagerDelegate {
   
    /// Location manager used to start and stop updating location.
    let manager = CLLocationManager()
    
    
    
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        manager.delegate = self
        
        manager.requestWhenInUseAuthorization()
        
        //start updating
        manager.allowsBackgroundLocationUpdates = true
        manager.startUpdatingLocation()
        
        //stop updating
        manager.stopUpdatingLocation()
        manager.allowsBackgroundLocationUpdates = false
    }
    
    /**
        Increases that location count by the number of locations received by the 
        manager. Updates the batch count with the added locations.
    */
    func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        receivedLocationCount = receivedLocationCount + locations.count
        locationBatchCount = locationBatchCount + locations.count

        locationBatchSizeLabel.text = String(locationBatchCount)
        
        receivedLocationCountLabel.text = String(receivedLocationCount)
    }
    
    /// Log any errors to the console.
    func locationManager(manager: CLLocationManager, didFailWithError error: NSError) {
        print("Error occured: \(error.localizedDescription).")
    }
}