MapKit and CoreLocation

Build map-based and location-aware features targeting iOS 17+ with SwiftUI MapKit and modern CoreLocation async APIs. Use Map with MapContentBuilder for views, CLLocationUpdate.liveUpdates() for streaming location, and CLMonitor for geofencing.

See references/mapkit-patterns.md for extended MapKit patterns and references/corelocation-patterns.md for CoreLocation patterns.

Contents

• Workflow
• SwiftUI Map View (iOS 17+)
• CoreLocation Modern API
• Geocoding
• Search
• Directions
• PlaceDescriptor (iOS 26+)
• Common Mistakes
• Review Checklist
• References

Workflow

1. Add a map with markers or annotations

1. Import MapKit.
2. Create a Map view with optional MapCameraPosition binding.
3. Add Marker, Annotation, MapPolyline, MapPolygon, or MapCircle inside the MapContentBuilder closure.
4. Configure map style with .mapStyle().
5. Add map controls with .mapControls { }.
6. Handle selection with a selection: binding.

2. Track user location

1. Add NSLocationWhenInUseUsageDescription to Info.plist.
2. On iOS 18+, create a CLServiceSession to manage authorization.
3. Iterate CLLocationUpdate.liveUpdates() in a Task.
4. Filter updates by distance or accuracy before updating the UI.
5. Stop the task when location tracking is no longer needed.

3. Search for places

1. Configure MKLocalSearchCompleter for autocomplete suggestions.
2. Debounce user input (at least 300ms) before setting the query.
3. Convert selected completion to MKLocalSearch.Request for full results.
4. Display results as markers or in a list.

4. Get directions and display a route

1. Create an MKDirections.Request with source and destination MKMapItem.
2. Set transportType (.automobile, .walking, .transit, .cycling).
3. Await MKDirections.calculate().
4. Draw the route with MapPolyline(route.polyline).

5. Review existing map/location code

Run through the Review Checklist at the end of this file.

SwiftUI Map View (iOS 17+)

import MapKit
import SwiftUI

struct PlaceMap: View {
    @State private var position: MapCameraPosition = .automatic

    var body: some View {
        Map(position: $position) {
            Marker("Apple Park", coordinate: applePark)
            Marker("Infinite Loop", systemImage: "building.2",
                   coordinate: infiniteLoop)
        }
        .mapStyle(.standard(elevation: .realistic))
        .mapControls {
            MapUserLocationButton()
            MapCompass()
            MapScaleView()
        }
    }
}

Marker and Annotation

// Balloon marker -- simplest way to pin a location
Marker("Cafe", systemImage: "cup.and.saucer.fill", coordinate: cafeCoord)
    .tint(.brown)

// Annotation -- custom SwiftUI view at a coordinate
Annotation("You", coordinate: userCoord, anchor: .bottom) {
    Image(systemName: "figure.wave")
        .padding(6)
        .background(.blue.gradient, in: .circle)
        .foregroundStyle(.white)
}

Overlays: Polyline, Polygon, Circle

Map {
    // Polyline from coordinates
    MapPolyline(coordinates: routeCoords)
        .stroke(.blue, lineWidth: 4)

    // Polygon (area highlight)
    MapPolygon(coordinates: parkBoundary)
        .foregroundStyle(.green.opacity(0.3))
        .stroke(.green, lineWidth: 2)

    // Circle (radius around a point)
    MapCircle(center: storeCoord, radius: 500)
        .foregroundStyle(.red.opacity(0.15))
        .stroke(.red, lineWidth: 1)
}

Camera Position

MapCameraPosition controls what the map displays. Bind it to let the user interact and to programmatically move the camera.

// Center on a region
@State private var position: MapCameraPosition = .region(
    MKCoordinateRegion(
        center: CLLocationCoordinate2D(latitude: 37.334, longitude: -122.009),
        span: MKCoordinateSpan(latitudeDelta: 0.05, longitudeDelta: 0.05)
    )
)

// Follow user location
@State private var position: MapCameraPosition = .userLocation(fallback: .automatic)

// Specific camera angle (3D perspective)
@State private var position: MapCameraPosition = .camera(
    MapCamera(centerCoordinate: applePark, distance: 1000, heading: 90, pitch: 60)
)

// Frame specific items
position = .item(MKMapItem.forCurrentLocation())
position = .rect(MKMapRect(...))

Map Style

.mapStyle(.standard)                                        // Default road map
.mapStyle(.standard(elevation: .realistic, showsTraffic: true))
.mapStyle(.imagery)                                         // Satellite
.mapStyle(.imagery(elevation: .realistic))                  // 3D satellite
.mapStyle(.hybrid)                                          // Satellite + labels
.mapStyle(.hybrid(elevation: .realistic, showsTraffic: true))

Map Interaction Modes

.mapInteractionModes(.all)           // Default: pan, zoom, rotate, pitch
.mapInteractionModes(.pan)           // Pan only
.mapInteractionModes([.pan, .zoom])  // Pan and zoom
.mapInteractionModes([])             // Static map (no interaction)

Map Selection

@State private var selectedMarker: MKMapItem?

Map(selection: $selectedMarker) {
    ForEach(