So, you have a smart phone? It does GSM or CDMA or LTE “cellular” wireless, but it probably does 802.11 wi-fi too, right?
You would not believe how eager your device is to spill its guts to anyone. As always, don’t take it from me. Here’s the NakedSecurity article:
http://nakedsecurity.sophos.com/2012/10/02/what-is-your-phone-saying-behind-your-back/