Technological progress, like authoritarian regimes, is insidious. Nothing big changes all at once; instead, a steady stream of smaller, less threatening changes occur over time. These alterations don’t sound alarm bells precisely because they blend into the fabric of our everyday lives. It is only when viewed en masse, through the prism of history, that it all appears to have been leading to an unwelcome outcome.

Kevin Byrnes’s chilling nonfiction thriller, Harvest, affords us that crucial step back. Filmed over seven days in March of 2016, it follows the daily life of a suburban woman named Jenni. She drops her kids off at school. She goes to work. She checks her email. She runs errands. Who cares?

Her iPhone, and the thousands of strangers to which it is constantly transmitting information. Through narration written from the perspective of the phone, Harvest explores the haunting extent to which Jenni is a woman watched—and so are we.

“By chance, one day, I discovered that my iPhone had a record of everywhere I had been,” Byrnes told The Atlantic. “As I began to investigate the third-party tracking facilitated by our mobile phones, I was reminded of narrated wildlife documentaries I watched as a child. I decide to take that basic concept in a new and unexpected direction with Harvest.”

Although Byrnes concedes that mobile phones offer unprecedented conveniences, he cautions against complacency. “I don’t think people are aware of what they are giving away in order to get these conveniences,” he continued. “I want people to think about the apps they use and take a moment to ask themselves if what they are getting is worth what they are giving. If not, delete the app. There are bigger issues at play, but it starts with this basic exercise.”