Heat Map is an overlay for the Map Kit Framework to visualize location-based datasets.
Using Heat Map in your project is simple. Create a new HeatMap object and pass it an NSDictionary, with NSValue keys encoded as MKMapPoints and NSNumber values representing the relative heat of that map point. You must also set your controller as the MKMapViewDelegate for your map view, and return a HeatMapView in mapView:viewForOverlay:.
There are a number of tweakable parameters in HeatMap and HeatMapView to alter the look and feel of the visualization. These are set through various #defines.
The dataset in the example app shows North American breweries, courtesy of POI Factory.
Thanks to Michael Stapelberg for his cCSVParse library used to pull in the brewery data.
Plans for future development include improving the performance of the visualization and doing some image filtering to improve the look/feel.