The proliferation of mobile devices and cost of GPS hardware implementations have raised interesting new methods for positioning end-points on the globe. IP address lookups are completely inaccurate (when in downtown Toronto near the lakeshore, one IP locator placed me near the 401, about 10km away.) I thought it was interesting that the iPod Touch OS doesn’t contain GPS (as its iPhone sibling), but instead uses Skyhook Wireless, a location lookup based on the (password secured or not) wireless router MACs within your range. Needless to say, it’ll only be accurate in dense urban areas. But almost pinpoint it is.
A post I made to Nine Inch Nails’ iPhone app after this week’s Toronto NINJA show placed my geotagged message within 50 metres of my location. If your PC has a wireless adapter, you can check out its power within your immediate location by using this live Skyhook Wireless demo (requires browser plugin installation.)
This raises interesting uses by cheaper open source applications, such as powerful geotagging of pictures uploaded to Flickr directly from a mobile phone. At my last job, I played with the Google Gears Geolocation API for calculating the distance of a logged in user to an event using a shipping address saved in their profile. This can be great, for instance, to filter out events not within a certain kilometre radius. It does bring up latency issues since Google Gears is client-side JavaScript, so all events must be retrieved from the database with filtering done in the browser (using an AJAX call for each event) so it isn’t very practical when a couple hundred current events exist at that moment. This is especially true because the haversine formula used for calculating distances between points while considered the curvature of the Earth is a taxing database query.
For this reason, wireless lookup is really made for small-scale apps with little data overhead. I just think it’s great that we can choose to use our existing public ground-based infrastructure to build impressive tools with little expense.
