New DoD policy: Deployed service members cannot use GPS-enabled devices

Instead, the memorandum instructs that the devices' geospatial tracking capabilities must be turned off in sensitive or unsafe operating areas where the exposure of location data could cause a "significant risk" to members of the military.

For all other locations, such as installations in the United States and overseas, "the heads of DoD components will consider the inherent risks associated with geolocation capabilities on devices, applications, and services, both non-government and government-issued, by personnel both on and off duty", the memo states.

"Effective immediately, DoD personnel are prohibited from using geolocation features and functionality on both non-government and government-issued devices, applications, and services while in locations designated as operational areas", Deputy Secretary of Defense Patrick Shanahan said in a memo to the leaders of departments within the Pentagon.

Military troops and Defense Department personnel deployed to sensitive areas such as war zones will no longer be able to use fitness trackers and cellphone applications that pinpoint their location. Audricia Harris told reporters that it was a blanket restriction on the devices at locations deemed as an "operational area", which could include ships out at sea, classified bases or warzones or hostile locations in Syria, Iraq, Afghanistan or parts of Africa. The Global Heat Map, published by the Strava fitness app, used satellite information to map the locations of subscribers to Strava's fitness tracking service. Within the U.S., the colorful web of lines was mostly just an interesting way of visualizing runners' data, but in Middle Eastern countries such as Afghanistan, the map showed much more.

"It goes back to making sure that we're not giving the enemy an unfair advantage and we're not showcasing the exact locations of our troops worldwide", said Army Col. Rob Manning, a Pentagon spokesman.

This is the second memo affecting the use of cellphones and other electronic devices that the department has released in recent months. But it also stopped short of banning the devices, and instead made clear that cellphones can still be used in common areas and other offices in the Pentagon if classified information is not present.

In other words, commanders may decide to restrict the use of geolocation capabilities on devices on areas of installations where "sensitive activities" are conducted, Harris said.

Military officials are set to create risk management guidelines and new training for those devices within 30 days, the report said.