> Do towers record past telemetry data? Yes. Did everyone forget about COTRAVELER? http://apps.washingtonpost.com/g/page/national/how-the-nsa-is-tracking-peop

> Do towers record past telemetry data? Yes. Did everyone forget about COTRAVELER? http://apps.washingtonpost.com/g/page/national/how-the-nsa-is-tracking-people-right-now/634/ http://apps.washingtonpost.com/g/page/national/how-the-nsa-i... > the granularity of knowing that a particular tower handled a phone ping is comparatively useless. No, it's not. A simple correlation with other phones tells you who is traveling together (co-travelers). This only requires knowing which phones are near each tower, at a fairly low temporal granularity. I'm sure there are additional ways to analyze that data, too. The travel and relationship map that COTRAVELER discovers is merely the project we know about.