As the tagline suggests, it shows your Google Location history visualized as a heatmap on an interactive map. E.g. My San Francisco location history: http://imgur.com/nN4frne, My now non-existent commute: http://imgur.com/WExNeBH
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This seems like a great tool. I can imagine there are a lot of other services that could benefit from the heat map and just import the data with the same structure as good.
As the tagline suggests, it shows your Google Location history visualized as a heatmap on an interactive map. E.g. My San Francisco location history: http://imgur.com/nN4frne, My now non-existent commute: http://imgur.com/WExNeBH
Shyp