Narrator: This is Science Today. Geotags are basically the technology that uses GPS in combination with wireless network footprints and cell tower information to pinpoint your location. Gerald Friedland of the University of California, Berkeley-affiliated International Computer Science Institute, explains that geotags are great on our smartphones when we dial 911 or if we're lost and need directions.
Friedland: The bad news is often these things are embedded without people knowing and then also, too many applications want this information.
Narrator: Friedland and his colleagues developed an app called "Ready or Not," which demonstrates how people, including crooks and stalkers, can easily track your location when you post a picture or send an update via social media. But, if you can't resist posting vacation pics in real time, Friedland says post PNG files instead of JPEG.
Friedland: PNG is an open standard and it does not allow for the excess metadata. So, the excess metadata that contains geotags is only in TIFF and JPEG files. That's just the easiest approach for everybody.
Narrator: For Science Today, I'm Larissa Branin.