I’ve been playing around a bit with GISCloud, a web-based GIS program. Looks interesting, and promising, but still has serious limitations. Feature set includes:
- Raster and vector data display
- Vector layer import and editing, including shapefiles, MapInfo, KML, tab-delimited and GPX
- Built-in datafile coordinate reprojection; recognizes prj files, and lets you select the output coordinate system (including the one for your current project)
- Advanced GIS analysis tools, including buffering, spatial selection by analysis, layer comparison (e.g. intersection), and area calculations.
- Export vector data layers in shapefile, MapInfo, CSV or KML; this makes it a handy online format converter.
- Share map editing with other users (or just publish it for viewing)
- Easy-to-decode classic-looking GIS interface:
On the downside:
- Only data layers imported into or through a PostGIS connection can be used for analysis and editing. I’m not up on PostGIS so I couldn’t test these functions, and none of the data sample sets have PostGIS data, either. You can apparently upload data and import it into a PostGIS database, though.
- Uploading files can take a while (though they’re saved locally); GISCloud recognizes files in compressed archives, so you’re best off zipping up your data before you upload it.
- For PostGIS data, I suspect that upload times are going to limit the size of the vector/database layers you can use.
- Apparently no thematic (attribute-based) display colors yet; this is a major drawback.
- Raster imagery updates during zooms can be slow.
- Not all raster image types supported (e.g. 8-bit indexed GeoTiffs don’t work, 24-bit do).
- It’s not exactly the zippiest GIS platform I’ve ever worked with.
- It’s Flash-based, so Flash haters and iPad users should avoid, and everyone should expect CPU/performance/crashing issues. Flash 10.1 is supposed to be out soon, and supposedly will address some of those problems.
An interesting early effort in cloud-based GIS, and I’ll be watching its development. But unless you have access to, and/or experience with, PostGIS, of limited utility for now. And I don’t expect to see cloud-based GIS replacing dedicated GIS programs any time in the near future – too slow, and too limited.