The payload was being activated whenever the phone was meeting a specific set of conditions: moving above 50mph, in a straight line, and on a road with a smooth surface.

When all three conditions were met a POST was made to an HTTP endpoint somewhere inside China. While the first two conditions are common, the detection of a well maintained highway with a suspicious lack of potholes is rare enough to identify secret military air fields with complete accuracy.

— me, after Doctorow