Although this is not specific to Android phones, it indeed does happen on Android phones. I am talking about the use of "diagnostic mode" in order to spy on all the background audio around your phone. Here is some more information: As early as 1997, the National Reconnaissance Organization warned that any mobile phone can be turned into a microphone and transmitter for the purpose of listening to conversations in the vicinity of the phone. This is basically done by transmitting to the mobile phone a maintenance command on the control channel. This command places the mobile telephone in 'diagnostic mode'. When this is done, conversations in the immediate area of the telephone can be monitored over the voice channel. So.... my question to Android Forums, is whether or not there is a way to prevent this. All the articles I have read on it mention a "maintenance command"... the "control channel" ... and "diagnostic mode"... So.. is it possible, using Android software, or hardware, or some method... is it possible to disable any of these things, in order to prevent this from happening... For example, could you disable remote activation of "diagnostic mode", in order to prevent this spying. This is separate from Carrier IQ, which can be removed by using a custom ROM, or an OS without Carrier IQ.... This is something, which, according to my quote above, has been known about since at least 1997, when everyone was using old-style mobile phones... So, what does everyone think? Is anyone an expert on this subject? Is there any way to prevent this method of spying?