A senator's letter confirms the U.S. military moved to prevent the tracking after foreign adversaries used location data to target troops.

New findings by the Electronic Frontier Foundation aim to warn app developers that some of the third-party code they place in their apps may also collect their users' location data when they grant permission to the app. 

Some lawmakers are calling for widespread reforms following years of surveillance scandals and abuses across successive U.S. administrations. But even if the spy law known as Section 702 expires on April 30, the government's spy powers will not automatically lapse.