Interesting read...
http://www.telegraph.co.uk/news/2018...ses-personnel/
A global map showing the distribution of people using personal fitness devices risks giving away troop movements and secret military facilities around the world, according to defence analysts who have already used it to pinpoint bases in Afghanistan and the Middle East. The American satellite navigation service Strava last year launched its Global Heat Map, a visualisation of user data showing the location of its 27 million subscribers including owners of Fitbit, Jawbone and Vitofit fitness monitors.
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