"Polar, a fitness app, is revealing the homes and lives of people exercising in secretive locations, such as intelligence agencies"

BC:

Compared to the similar services of Garmin and Strava, Polar publicizes more data per user in a more accessible way, with potentially disastrous results.

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By showing all the sessions of an individual combined onto a single map, Polar is not only revealing the heart rates, routes, dates, time, duration, and pace of exercises carried out by individuals at military sites, but also revealing the same information from what are likely their homes as well. Tracing all of this information is very simple through the site: find a military base, select an exercise published there to identify the attached profile, and see where else this person has exercised. As people tend to turn their fitness trackers on/off when leaving or entering their homes, they unwittingly mark their houses on the map. Users often use their full names in their profiles, accompanied by a profile picture — even if they did not connect their Facebook profile to their Polar account.

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With only a few clicks, a high-ranking officer of an airbase known to host nuclear weapons can be found jogging across the compound in the morning. From a house not too far from that base, he started and finished many more runs on early Sunday mornings. His favorite path is through a forest, but sometimes he starts and ends at a car park further away. The profile shows his full name.