I do realize the info below is a bit technical, but that’s the best way for me to share what I’ve figured out so far at this point. Please feel free to let me know if you discover something else here.
Carrier IQ is run from a number of different daemons, depending on the firmware version of the device: (You can view this on a jailbroken iPhone with iFile or extract it from a software update bundle if you want to check the files out yourself.)
iOS 3: /usr/bin/IQAgent
iOS 4 and 5: /usr/bin/awd_ice2 or /usr/bin/awd_ice3
The startup routine verifies that it is running on either a compatible device and exits if it is not. In addition, and most importantly: it appears it will only run if:
iOS 3: The DiagnosticsAllowed key is set to true in the com.apple.iqagent preferences — which it does not appear to be enabled on any of my devices. (If anyone knows what would cause this key to be set to true, please let me know.)
iOS 4: Unknown, probably like iOS 3.
iOS 5: Copies the ShouldSubmit value from lockdownd, under the domain com.apple.MobileDeviceCrashCopy. I believe this value is set by the “Submit Logs to Apple” option during the iOS 5 setup sequence, and so Carrier IQ logging is toggled with that setting.
There is also a check to ensure that your carrier supports the logging: it appears some carriers support it only over WiFi, others over 3G. However, despite those restrictions and never enabling the above checks, I do see Carrier IQ log files stored on all of the devices I tested:
iOS 3: /var/logs/IQAgent
iOS 4: /var/wireless/Library/Logs/IQAgent
iOS 5: /var/wireless/Library/Logs/awd
But is this version of Carrier IQ the same keylogger/rootkit as on Android? The answer appears to be: not quite. It does access a reasonable amount of information, however: (Be sure to note that I have not confirmed which, if any, of this data is sent remotely.)
your phone number
active phone calls
(However, I only saw it noting that a phone call was active, not what number was dialed or it was received from. But, I am not going to claim it doesn’t do that: it’s certainly possible, but didn’t see it.)
your location (Only, however, if Location Services are enabled.)
(Possibly more I haven’t yet found.)
As Carrier IQ claims in their video, communication with the remote server is all done via SSL. Importantly, it does not appear the daemon has any access or communication with the UI layer, where text entry is done. I am reasonably sure it has no access to typed text, web history, passwords, browsing history, or text messages, and as such is not sending any of this data remotely.
It appears that if you really care about this, Windows Phone 7 is the only mobile operating system without this installed. ;P However, I think the blame here really belongs with the US carriers who obviously demanded this: personally, I am completely fine with this data being sent off (especially if it helps AT&T’s network improve), but I would definitely prefer if it was more transparent — even if you can disable it with that toggle, Apple only explains that it “might contain location data”.