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iPhone fireflies flicker across Europe in time-lapse video


Flickering like fireflies as they blink in and out of existence, this rather hypnotic animation is actually a visualisation of the movement of iPhones (and their owners, presumably) over the course of one month.

The time-lapse video tracks the movement of 880 iPhones across western Europe, mostly Germany and the UK, in April 2011. The data was uploaded to the CrowdFlow site by volunteers using the same iPhone data log that caused such a fuss a few months ago.

Michael Kreil and colleagues at the site are trying to create an open source record of Wi-Fi and cellphone networks around the world so they can be used in research. In comments on the site's blog, Kreil explains why the points of light fade in and out of focus.

"The geo data of the iPhones are quite accurate, but I only know the locations at specific points in time. So for example I know the accurate position of an iPhone at 12:03 and at 14:27 but I have no clue, how this iPhone had moved in the meantime. So my estimation is that an iPhone moves from the last known location at an average speed of 30km/h - in all possible directions. It's like a diffusion process. That's why the estimated location becomes more and more blurry and the light fades away."

The same reasoning explains why the pinpricks of light become more diffuse overnight: there's no new information on the phone's location and so its likely whereabouts becomes less and less certain as the hours pass.

It's just nice to see that troublesome iPhone location file being put to some sort of good use. Expand to full screen, cue up some suitably jazzy music, and enjoy.

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