title: Unable to detect Beacon device when iPhone sleeps.(goes background)
body: <p>I am trying to detect iBeacon devices from Application on iPhone.</p>
  
  <p>It detects iBeacon device while running, but when I lock an iPhone, 
  it cannot detect (lose) the same iBeacon device.
  (Proximity:Unknown RSSI:0 Accuracy:-1.0)
  It can detect other device as Android (App:Locate Beacon) on the same condition.</p>
  
  <p>Can anyone help me to find the reason and solution?</p>
  
  <p>Note:</p>
  
  <p>iPhone &lt;=> iBeacon device Fail
  iPhone &lt;=> Android (App:Locate Beacon/iBeacon) Ok</p>
  
  <p>Android:AltBeacon does good for same device.</p>
  
  <p>Android &lt;=> iBeacon device Ok</p>