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diff --git a/platform/ios/demo/Examples/Swift/RuntimeAddLineExample.swift b/platform/ios/demo/Examples/Swift/RuntimeAddLineExample.swift
new file mode 100644
index 0000000000..62b3d869c1
--- /dev/null
+++ b/platform/ios/demo/Examples/Swift/RuntimeAddLineExample.swift
@@ -0,0 +1,90 @@
+import Mapbox
+
+@objc(RuntimeAddLineExample_Swift)
+
+class RuntimeAddLineExample_Swift: UIViewController, MGLMapViewDelegate {
+    var mapView: MGLMapView!
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+
+        mapView = MGLMapView(frame: view.bounds)
+        mapView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
+
+        mapView.setCenter(
+            CLLocationCoordinate2D(latitude: 45.5076, longitude: -122.6736),
+            zoomLevel: 11,
+            animated: false)
+        view.addSubview(mapView)
+
+        mapView.delegate = self
+    }
+
+    // Wait until the map is loaded before adding to the map.
+    func mapView(_ mapView: MGLMapView, didFinishLoading style: MGLStyle) {
+        loadGeoJson()
+    }
+
+    func loadGeoJson() {
+        DispatchQueue.global().async {
+            // Get the path for example.geojson in the app’s bundle.
+            guard let jsonUrl = Bundle.main.url(forResource: "example", withExtension: "geojson") else { return }
+            guard let jsonData = try? Data(contentsOf: jsonUrl) else { return }
+            DispatchQueue.main.async {
+                self.drawPolyline(geoJson: jsonData)
+            }
+        }
+    }
+
+    func drawPolyline(geoJson: Data) {
+        // Add our GeoJSON data to the map as an MGLGeoJSONSource.
+        // We can then reference this data from an MGLStyleLayer.
+
+        // MGLMapView.style is optional, so you must guard against it not being set.
+        guard let style = self.mapView.style else { return }
+
+        let shapeFromGeoJSON = try! MGLShape(data: geoJson, encoding: String.Encoding.utf8.rawValue)
+        let source = MGLShapeSource(identifier: "polyline", shape: shapeFromGeoJSON, options: nil)
+        style.addSource(source)
+
+        // Create new layer for the line
+        let layer = MGLLineStyleLayer(identifier: "polyline", source: source)
+        layer.lineJoin = MGLStyleValue(rawValue: NSValue(mglLineJoin: .round))
+        layer.lineCap = MGLStyleValue(rawValue: NSValue(mglLineCap: .round))
+        layer.lineColor = MGLStyleValue(rawValue: UIColor(red: 59/255, green:178/255, blue:208/255, alpha:1))
+        // Use a style function to smoothly adjust the line width from 2pt to 20pt between zoom levels 14 and 18. The `interpolationBase` parameter allows the values to interpolate along an exponential curve.
+        layer.lineWidth = MGLStyleValue(interpolationMode: .exponential,
+            cameraStops: [14: MGLStyleValue<NSNumber>(rawValue: 2),
+                          18: MGLStyleValue<NSNumber>(rawValue: 20)],
+            options: [.defaultValue : MGLConstantStyleValue<NSNumber>(rawValue: 1.5)])
+
+        // We can also add a second layer that will draw a stroke around the original line.
+        let casingLayer = MGLLineStyleLayer(identifier: "polyline-case", source: source)
+        // Copy these attributes from the main line layer.
+        casingLayer.lineJoin = layer.lineJoin
+        casingLayer.lineCap = layer.lineCap
+        // Line gap width represents the space before the outline begins, so should match the main line’s line width exactly.
+        casingLayer.lineGapWidth = layer.lineWidth
+        // Stroke color slightly darker than the line color.
+        casingLayer.lineColor = MGLStyleValue(rawValue: UIColor(red: 41/255, green:145/255, blue:171/255, alpha:1))
+        // Use a style function to gradually increase the stroke width between zoom levels 14 and 18.
+        casingLayer.lineWidth = MGLStyleValue(interpolationMode: .exponential,
+            cameraStops: [14: MGLStyleValue(rawValue: 1),
+                          18: MGLStyleValue(rawValue: 4)],
+            options: [.defaultValue : MGLConstantStyleValue<NSNumber>(rawValue: 1.5)])
+
+        // Just for fun, let’s add another copy of the line with a dash pattern.
+        let dashedLayer = MGLLineStyleLayer(identifier: "polyline-dash", source: source)
+        dashedLayer.lineJoin = layer.lineJoin
+        dashedLayer.lineCap = layer.lineCap
+        dashedLayer.lineColor = MGLStyleValue(rawValue: .white)
+        dashedLayer.lineOpacity = MGLStyleValue(rawValue: 0.5)
+        dashedLayer.lineWidth = layer.lineWidth
+        // Dash pattern in the format [dash, gap, dash, gap, ...]. You’ll want to adjust these values based on the line cap style.
+        dashedLayer.lineDashPattern = MGLStyleValue(rawValue: [0, 1.5])
+        
+        style.addLayer(layer)
+        style.addLayer(dashedLayer)
+        style.insertLayer(casingLayer, below: layer)
+    }
+}