Here are some of the biggest reveals from a fitness-tracker data map that may have compromised top-secret US military bases around the world

A fitness app called Strava updated the 2017 exercise routes of more than one billion people over the weekend.

In the process, Strava may have inadvertently revealed the locations and activities of US troops in secret bases around the world.

The Strava app takes data from fitbits and smartphones, uploading the information to a "heatmap" for users to track their workouts and share with friends.

People from all around the world use the app, and could prove problematic for a number of foreign militaries. But since the app is used mostly by young westerners, the US military has the most to lose, given its large global footprint.

Here are 10 of the most revealing images from the heatmap: