Overview

Markers and annotations

Mapbox offers a few different ways to add markers to a map, each with different tradeoffs. Below is an overview of the variety of approaches that can be used.

Annotations

Our annotations API includes the MGLAnnotationImage, and MGLAnnotationView classes. These are most similar to MapKit’s annotation class and provide a familiar interface for working with markers and callouts.

MGLAnnotationImage
MGLAnnotationView

MGLAnnotationImage is an annotation class that is easily customizable with any UIImage. It is highly performant, as the images are rendered directly using OpenGL. However, if you need to animate your annotations or control z-layer ordering, consider working with MGLAnnotationView which supports any animation that can be applied to a UIView. View hierarchy can be manipulated by using instance methods available on UIView such as -[UIView bringSubviewToFront:].

MGLAnnotationView is an annotation class that is an easily customizable UIView. Use this class if you need your markers to be dynamic or animated. MGLAnnotationView has a significant advantage over MGLAnnotationImage when you need every annotation to be unique. For example, annotation views are ideal for showing user locations on a map using high-resolution profile pictures. However, the map can slow down when many annotation views are visible at the same time, so if you need to add a very large number of markers, consider using our runtime styling APIs instead.

Both MGLAnnotationImage and MGLAnnotationView can become interactive by adding a few lines of code. When the user taps an annotation, the annotation’s name appears in a basic callout. An annotation view can additionally respond to drag-and-drop gestures.

Runtime styling

For full control of how markers are displayed on a map, consider using our runtime styling APIs. Like MGLAnnotationImage, it is a performant approach to adding markers because they rendered directly using OpenGL. However, the runtime styling APIs also provide support for rendering labels together with icons, finer control of z-ordering, and clustering, so consider using this set of APIs if you need to display a large amount of highly customizable markers.

Our runtime styling API is the most powerful option if you need to create rich data visualizations within in your map, but it is the most complex and has a steeper learning curve than our annotations API.

The runtime styling API includes our MGLSymbolStyleLayer and MGLCircleStyleLayer classes that can be used to dynamically display on markers on map when used in conjunction with either an MGLVectorSource or an MGLShapeSource.

If you need to implement callouts with the MGLSymbolStyleLayer or MGLCircleStyleLayer, you will need to implement your own tap gesture recognizer that calls -[MGLMapView visibleFeaturesAtPoint:inStyleLayersWithIdentifiers:] to get the tapped point feature, then show a UIView you provide. Additionally, if you need to animate markers when using the runtime styling APIs, consider using a timer to update the source data coordinates accordingly.

MGLCircleStyleLayer
MGLSymbolStyleLayer

The MGLCircleStyleLayer class is the style layer class responsible for displaying the source’s point features as circle-shaped markers. You can specify circle fill and outline colors, as well as size. You can also dynamically change the circle’s styling properties based on any attributes your source data contains.

The MGLSymbolStyleLayer class is the style layer class responsible for displaying the source’s point features as icons and labels. You can use custom images as icons and also combine text labels, placing them exactly where you specify. You can also dynamically change the symbol’s styling properties based on any attributes your source data contains.

Still undecided on which approach will work best for your use case? Reach out to our support team.

See the table below for a summary of APIs that can be used to add markers to a map:

✅ Recommended

⚠️ Supported with caveats

➖ Unavailable or not supported

FeatureMGLAnnotationViewMGLAnnotationImageMGLSymbolStyleLayerMGLCircleStyleLayer
Customizability
Text labels, interactive subviews
⚠️
Static images only

Full support for text labels and label placement

Customize circle color and outline
Borrows familiar concepts fromMapKit, Google Maps SDKMapbox GL JS, Mapbox StudioMapbox GL JS, Mapbox Studio
Can use images


Can use text

Control Z-index
⚠️
Add multiple layers at, above, or below a specified layer index to control ordering
⚠️
Add multiple layers at, above, or below a specified layer index to control ordering
Drag and drop
Core Animation support
Add/move/replace

⚠️
Partial data updates are less performant than using annotations
⚠️
Partial data updates are less performant than using annotations
SceneKit support
Can be dynamically styled based on data attributes
Subclass
MGLPointAnnotation
to add custom attributes

Subclass
MGLPointAnnotation
to add custom attributes


Supports callouts
Built-in callouts included

Built-in callouts included
⚠️
Implement your own gesture recognizer that uses feature querying, then create custom UIViews to mimic native callouts
⚠️
Implement your own gesture recognizer that uses feature querying, then create custom UIViews to mimic native callouts
Supports clustering⚠️
Use a
third-party plugin