Now this is a tutorial you should bookmark for next time you need to display point info on a MapKit map:
This tutorial will demonstrate how to handle and display thousands of points of data on an iOS map in a way people understand and enjoy.
We are going to make an iOS app which ships with 87,000 hotels, each with a coordinate, a name and a phone number. This app will never ask the user to “redo search in area”; it will update the map as the user pans and zooms, allowing the user to freely explore the data.
This will require us to come up with an ultra quick data structure built for the task. We will need to build it in C for it to be performant. Once we have constructed our data structure we will come up with a clustering system, as to not overwhelm the user. Finally, we will give it the professional polish that is required for apps to compete in today’s market…
That is one seriously detailed tutorial. Check out the accompanying app at thoughtbot / TBAnnotationClustering!
h/t: iOS Dev Weekly!
choefele / CCHMapClusterController implements this as a simply usable component.