The Timeline feature in Google Maps is a pretty interesting way to track your whereabouts throughout a day.
For me, I especially like to check it out whenever I am walking around a lot to see how much ground in a city I have covered. One thing that would be even more interesting to see is that data aggregated over a certain timeperiod, so you can see how much of a city you have visited in a given time.
Google Maps' Timeline doesn't have this feature, so I thought it might be neat to build a quick visualizer for this.