I recently heard the CIO of the CIA tell an audience the battery had to be out for you to not be tracked.
http://www.huffingtonpost.com/larry-bodine/big-brother-is-definitely_b_1799521.html
https://ssd.eff.org/wire/protect/cell-tracking
http://beforeitsnews.com/survival/2012/12/how-stop-your-phone-from-being-tracked-2454408.html
http://www.propublica.org/article/thats-no-phone.-thats-my-tracker
You’re welcome.