http://www.engadget.com/2011/12/01/carrier-iq-what-it-is-what-it-isnt-and-what-you-need-to/
Carrier IQ is a diagnostic tool some carriers and phone manufactures put on their phones to help diagnose problems the phone may be having. The carriers and manufactures can customize the tool to capture specific types of data and events. However someone has found out this tool is very powerful and is capable of capturing pretty much everything you do on the phone, keystrokes, messages, calls, and more. And not only can it capture all of this over the carriers 3G, it also monitors the wifi too.
Sprint and a number of manufactures are known to use it, but more are unconfirmed and suspected as well. Verizon says they don't use it. AT&T and T-Mobile haven't seen mentioned yet.
It's definitely got people stirred up. In normal conditions I don't think it's a concern. I doubt T-Mobile is tracking my every keystroke. But if such a powerful diagnostic tool were to become compromised by some piece of malware, that's definitely scary.
