I suppose the most obvious thing about any successful application is how flexible enough it is to allow users to take it and do whatever they want with it. You cannot predict how people would like to use whatever tools you give them, so nothing beats having something fun and addictive, and letting users play around with it until something clicks.

Like Google Maps, for example, which has the power of showing everyone with a computer and an Internet connection the earth they live on and quite a lot of things about its geography.

Of late, projects have been done to show the state of the earth, particularly with reference to environmental change. It is interesting, because with Google Maps, you are not just being told where these environmental changes are taking place, you are the one who is rotating the globe and interactively choosing the places you are interested in seeing. Also, it is not just one or two examples, if the map is any good, it would have a good coverage of different places and climates around the world, so you feel involved and it is also an all-rounded picture of the situation.

What I like about the addons to Google Maps especially is how there are a number of them, all revealing different types of data. For example you could compare climate change with political and economic information to see how it all goes hand-in-hand.

Here is a page with some good links just so you know what I mean.

Check it out here