SpeakFree is a tool for jamming physical recording of conversations, and helping users keep their privacy in the real world.
When active, SpeakFree emits loud and random noises to mask your conversation. This not only prevents your phone microphone from working, but will make your voice indecipherable to microphones on nearby laptops, phones, and tablets.
The app also displays tips for protecting your physical privacy, to augment the microphone jamming.