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Do towers record past telemetry data? Assuming they do, the granularity of knowing that a particular tower handled a phone ping is comparatively useless. A guessed location (stored on the iPhone) based off of cell tower triangulation and the occasional GPS calculation is far more valuable.

I do agree that we should consider the FBI's statement with skepticism.

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> Do towers record past telemetry data?

Yes. Did everyone forget about COTRAVELER?

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.

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