“Facebook does not use your phone’s microphone to inform ads or to change what you see in News Feed,” Facebook spokesperson Joe Osborne said via email. “We do not show ads based on what you are talking about out loud.” Facebook does, however, request access to your microphone — for posting videos or making calls using Facebook Messenger. If you do not use either of those features, it’s easy to keep it turned off through Facebook settings on your mobile device. On iPhone, go to Settings > Privacy > Microphone > Facebook (and you might as well do Messenger and Instagram while you are there too.) On Android, go to Settings > Apps > Facebook > Permissions > Disable microphone.