Some facts about shingles include that: 1  Shingles is rare in children under ten years of age. 2  Younger children who do develop shingles tend to have milder symptoms than adults with shingles. 3  People have a 10 to 15 percent chance of developing shingles at some point in their life if they once had chicken pox.
There are approximately 310 million people in the United States. Of these people, approximately 250 million are over the age of 14. According to Comscore, about 235 million of these Americans use mobile devices. It seems likely that almost all of these folks will eventually have smartphones.
Tracking cell phones for everyone in the US: There are 271,000,000 cell phones in the US. There are on the order of 10^6 cell towers. A datagram containing a unique ID for each phone and a unique ID for the tower nearest that phone could therefore store each of those IDs in 32b, for a total packet size of 64b or so.