There have been plenty of stories of malware eavesdropping over smartphone microphones in the last two years. I doubt Facebook does it with their app. It's to

There have been plenty of stories of malware eavesdropping over smartphone microphones in the last two years. I doubt Facebook does it with their app. It's too much trouble, blatantly illegal and easy to get caught. It's most likely malwAre selling the info to fb, who has no idea how any advertisers get their info.