OpenScales is an open source mapping framework for ActionScript 3 and Flex. Supporting a range of OGC data protocols, it has many similarities to the OpenLayers framework but uses Flash rather than JavaScript. The combination of Flash, 'tweening', and fast data providers results in a smoother, more compelling user experience - remniscent of Bing Map's new Silverlight control.

This article was previously published on GeoChalkboard, and has been reproduced here with permission. GeoChalkboard is published by Geospatial Training Services who provide a range of geospatial web courses.

Google Maps provides a web mapping application wherein maps are produced in advance and served as a set of small tiles for assembly into one big image in the browser. The advantage of this approach is consistency of appearance and graphical quality of the map and, probably more important, enormous scalability that can be achieved. There is no need for server side processing to generate maps and individual map tiles are much smaller than the whole map presented at the user end, so they are able to be delivered and displayed much faster. The trade off is a big effort up front to generate nice looking maps and the need to fix zoom levels rather than allowing a continuous zoom, as is the case with older web mapping technologies. The approach has been copied by other online map technology providers. But what approach should you take if you’d like to present your own custom data on top of a Google Maps base layer without using markers, polylines, or polygons? Perhaps you have a large dataset stored in a shapefile and you’d simply like to convert this data to a format suitable for display in Google Maps. In this case it would make sense to pre-create custom map tiles of your data at various zoom levels and have them available for display.

The Google Maps Data API is a web service that allows client applications to view, store, and update  map data for Google Maps, using the Google Data API. Data is stored in the form of individual features and collections of features.

Full pricing information has yet to be released, but the service is currently free for publically-visible data.