When I posted about lib-flickr-minimal, I noted that the newly-launched flickr.places.placesForUser method made a more interesting demo of data you could fetch when authenticated than, say, showing a user's most recent private photos. Evidently the developers at Flickr agreed it was an interesting concept, because over the last couple of months that area of the API has been extended considerably, As a result, I've expanded the demo into an AppJet application of its own.
Where? What? When? is the result. It shows you, on a map, the locations with the most photos according to a given criterion: by default, that's a tag, but it can also show your photos, or those from your friends and family, or your contacts. You can then inspect a place and see the most recent relevant photos, or the most popular tags, for that location.
How did that evolve from the initial demo app? Instead of simply printing a table based on Flickr's response into the document, I directly plotted the results on the map. I added a small form to enable the choice of criteria, and when Flickr added the placesForTags method, I added that as a choice. Belatedly, I realised that would also work for users without authentication, so I removed the requirement to authenticate, and made tags the logged-out default. (The image above shows a slight change to the initial results: it's the same tag, London, but at the neighbourhood, not locality, level. All of the locations are within the greater city's area, which probably won't be a surprise, but that's not true for Paris. Evidently, what happens in Vegas doesn't always stay there.)
The design of the application isn't quite settled, but I knew I wanted to replace the standard Google Maps pushpins with partially-transparent circles. Initially, I went with red, but when I showed it to colleagues, they said it reminded them of maps of bomb blast radii, so I spent a while looking around for the right colour, before settling on a yellow. The circles themselves are scaled according to the natural log of the number of photos for that location; I played with square roots as well, but I feel that logarithms give the right sense of scale.
The last piece of work I did was adding tag display for locations, using the tagsForPlace method. These tags can be surfed: clicking on one will load a new search for the given tag. It's noticable that the first few tags for most places are almost always place names, while common tags seem to share a familiar pattern of scattered, similarly-sized circles across the US, Europe, south-east Asia and coastal Australia.
There's still a few things I could add; tag persistence in URLs (to make it easier to share pages), better loading indicators (especially initially), options on which photos are shown, and links to view the search on Flickr itself, for example. There's also a missing question: while the API methods support maximum and minimum times, I haven't yet added options to allow you to show When? However, for now I think I've done enough (and I'll note that the site has a link to view the source of the application, if you fancy hacking on it yourself.) Enjoy.