Scores on the doors
When you go out to eat you want to know that the people preparing your food have a good standard of food hygiene. Across England, Northern Ireland, and Wales the Food Standards Agency collate hygiene ratings from local inspectors and publish them as an open dataset. It is a great, consistent, dataset and we already include extracts of it on our Data Mapper e.g. food hygiene ratings for Leeds.
To protect privacy, the user's location is not sent out of the page so our web server never knows the user's precise location. Instead, the user selects a local authority and we send every food establishment in that local authority to the browser. That means the user has to select the correct local authority and it is a bit slower to load initially but those are the trade-offs to protect privacy.
Location, location, location
One problem I've noticed is that the location of the premises is sometimes off. That is because the FSA have determined the location by using the postcode centroid. This relies on the correct postcode being assigned and it also limits the accuracy with which a premises can be located. Sometimes a cafe/restaurant/pub might be listed up to 200m or so away from where it really is. It may be possible to improve locations by matching establishments to those included in Open Street Map data. However, the inconsistency of spellings and puncuation in both datasets will likely make that quite hard. It is something I'll try in the future.
The project currently covers Bradford, Calderdale, Kirklees, Leeds, Wakefield, Harrogate, and York.