Have you ever wanted to hear what people say about you when you walk out of the room? Well, you can if you have an iPhone. A secret Apple feature lets you leave your device in a room and eavesdrop on people’s conversations, and it only takes a second to set up. Secret iPhone ‘spy trick’It’s called Live Listen, which turns your iPhone or iPad into a microphone that sends sound to your AirPods or Beats. It doesn’t work with any other wireless headphones. The feature is designed to help you hear a conversation in a noisy area or someone speaking across the room. However, people have discovered it…