Is it possible that someone can hear my cell phone conversation ?
It is possible to eavesdrop on just about any telephone conversation, especially cell phones. However, not many private citizens have the technology to do so. I spent a long time in both the military and then in law enforcement. During training in the military on certain types of radio equipment we were able to pick up on both random and specific cell phone conversations, but it’s not something that is done very often. We certainly didn’t target anyone deliberately without the proper authorisation. I highly doubt that this is what is happening in your case. I also doubt that anyone who is not associated with an intelligence agency has the ability to listen in, nor could I see why anyone would want to.
