How to detect if a bluetooth headset plugged or not IOS 8?

You can detect currently active bluetooth output devices (instead of input devices)

Swift Code:

import AVFoundation
func bluetoothAudioConnected() -> Bool{
  let outputs = AVAudioSession.sharedInstance().currentRoute.outputs
  for output in outputs{
    if output.portType == AVAudioSessionPortBluetoothA2DP || output.portType == AVAudioSessionPortBluetoothHFP || output.portType == AVAudioSessionPortBluetoothLE{
      return true
    }
  }
  return false
}

Bluetooth devices are based on the following question: What's the difference among AVAudioSessionPortBluetoothHFP, A2DP and LE?

I hope it helps someone

---

Edit for Swift 5.1

func bluetoothAudioConnected() -> Bool {
    return !AVAudioSession.sharedInstance().currentRoute.outputs.map( {
        $0.portType == .bluetoothA2DP ||
        $0.portType == .bluetoothHFP ||
        $0.portType == .bluetoothLE
    }).isEmpty
}

I was able to detect whether a bluetooth headset (HFP) device was currently connected using the following:

NSArray *arrayInputs = [[AVAudioSession sharedInstance] availableInputs];
for (AVAudioSessionPortDescription *port in arrayInputs)
{
    if ([port.portType isEqualToString:AVAudioSessionPortBluetoothHFP])
    {
        bHas = YES;
        break;
    }
}

However, your AVAudioSession category must be set as AVAudioSessionCategoryPlayAndRecord in order for this to work. If it isn't, the port will not show up in the list even if the HFP device is connected.