How to get front camera, back camera and audio with AVCaptureDeviceDiscoverySession

You can get the front camera with the following:

AVCaptureDevice.default(.builtInWideAngleCamera, for: AVMediaType.video, position: .front)

The back camera:

AVCaptureDevice.default(.builtInWideAngleCamera, for: AVMediaType.video, position: .back)

And the microphone:

AVCaptureDevice.default(.builtInMicrophone, for: AVMediaType.audio, position: .unspecified)

Here's my code (Swift 3) to get camera position :

// Find a camera with the specified AVCaptureDevicePosition, returning nil if one is not found
func cameraWithPosition(_ position: AVCaptureDevicePosition) -> AVCaptureDevice?
{
    if let deviceDescoverySession = AVCaptureDeviceDiscoverySession.init(deviceTypes: [AVCaptureDeviceType.builtInWideAngleCamera],
                                                          mediaType: AVMediaTypeVideo,
                                                          position: AVCaptureDevicePosition.unspecified) {

        for device in deviceDescoverySession.devices {
            if device.position == position {
                return device
            }
        }
    }

    return nil
}

If you want, you can also get the new devicesTypes from iPhone 7+ (dual camera) by changing the deviceTypes array.

Here's a good read : https://forums.developer.apple.com/thread/63347

Swift 4, iOS 10+ and Xcode 10.1 replaces

if let cameraID = AVCaptureDevice.default(.builtInWideAngleCamera, for: .video, position: .front)?.localizedName {
       //cameraID = "Front Camera"
}

with AVCaptureDevice.DiscoverySession implementation

if let cameraID = AVCaptureDevice.DiscoverySession.init(deviceTypes: [AVCaptureDevice.DeviceType.builtInWideAngleCamera], mediaType: .video, position: .front).devices.first?.localizedName{
        //cameraID = "Front Camera"
} 

Need to wrap it with #available(iOS 10,*) check.