GeoCommons is provided by FortuisOne and builds on their software products to provide a free and public community service. GeoCommons currently provides two  easy-to-use free services based on open source and other freely available datasets. GeoCommons Maker is a simple point-and-click map creator that does not require programming experience; and GeoCommons Finder is a data uploading and sharing service with some basic geocoding abilities.

Although these tools are remarkably easy to use, GeoCommons Maker makes the mistake of using the Mercator projection for geospatial data visualization.

FortiusOne provide a range of browser-based  visual solutions geospatial analytical applications. The GeoCommons community is a free, community service based on their commercial solutions.

At the moment, GeoCommons consists of two services. Maker is a point-and-click map creator; and Finder is a geocoding service. Both services are free and remarkably easy to use.

GeoCommons Maker

GeoCommons Maker really is very easy to use, within a couple of minutes of signing up, I had created the following map of US Bear Attacks and Earthquakes (!):

Dialog boxes and tabs are usually self explanatory and easy to use. Documentation is provided, but this strikes me as being more useful to highlight non-obvious features rather than to show you how exactly to do something. It also uses some names which you might not see in the working application.

Base maps are road maps with tiles provided by OpenStreetMaps, Google Maps, Yahoo Maps, or Bing Maps. A number of map types are possible including points, areas, shaded areas, and sized circles.

Datasets are provided by a number of 'free' sources (eg. the earthquake data is from the US Geological Survey), but you can also import your own data using GeoCommons Finder.

Maker is implemented using Flash. This is used effectively and provides a responsive interface (my PC was running at >80% on an unrelated computation and the interface was still pretty quick). Although Flash is fashionable for web mapping at the moment, many people think its days are numbered. It also means it will not work with the Apple iPad. This is a shame as the easy-to-use interface seems an obvious application for a tablet device that lacks a keyboard.

Of course an interface like this that makes it easy create maps also limits what you can do and what can be customized. Although you cannot customize the map in the same way as you can customize a Google Maps or Bing Maps application, this is just a data presentation tool. It is not intended as the base of a map doodling tool or for navigation.

A more serious problem is the choice of map projection. GeoCommons Maker is a geo-visualisation tool and yet it uses the Mercator projection!! I have covered the mis-use of the Mercator projection for geostatical applications before
( URL:  ) and it is major problem for a data visualisation tool like this. I just hope FortuisOne do not make this mistake with their commercial products and services.

GeoCommons Finder

GeoCommons Finder consists of a data search engine of the available community data and layers. This was used for above Bears example. The availability of this data is useful but relatively limited. GeoCommons Finder also allows you to upload, map, and share your own geospatial data.

Finder's upload function covers a range of general purpose and geospatial offline and web formats, with support for 'spreadsheet' CSV (comma separated value) files, ESRI Shapefiles, KML, GeoRSS, RSS, ATOM, and plain text files. As well as files, Finder can load data from a URL, but this option is currently limited to traditionally online formats only (KML, GeoRSS, RSS, and ATOM). The upload function also supports 'batch' (ie. multiple file) uploads.

Many of these data formats require geocoding, and Finder supports a geocoder that is currently in an initial 'alpha' release. As it matures, the geocoder should become an important part of Finder.

Finder offers the GeoJoin feature to tie uploaded data to existing boundary datasets - eg. to produce "shaded area" choropleth maps. This kind of mapping isually limited to offline applications (eg. Microsoft MapPoint) due to the large size of most boundary datasets.

Finally Finder supports dynamic map updates from data feeds. Such a map would automatically display the current display-time data. This could be very useful for real time feeds - eg. earthquake data, or vehicle locations.

So overall, the GeoCommons Finder is a useful data collation and sharing tool that is integrated with GeoCommons Maker. The wide range of supported data formats and a number of less-common features make it a very useful tool. At the present time, the alpha status of the Geocoder is the only 'black mark', but this should be corrected in the near future as teh geocoder matures.