This device distorts the signals to and from all cell phones within a certain radius of you. Perhaps your hearing radius (i.e. anything within hearing distance).

It also prevents new calls from coming in. That way, you won’t have to put up with the annoying ringtones of all the cell phones around you.

It is great for movie theaters, libraries, and even cars.

I don’t know if this device exists already, or if it would be illegal. If it exists, it should be marketed more strongly. If it’s illegal, a legal version should be made that follows all the rules.