title: Re-Connect BLE device in background iOS
body: <p>My app can connect in foreground to BLE devices. But BLE device doesn't re-connect again after disconnect device while the app is in background. I added required permission in info.plist :</p>
  
  <pre><code>&lt;key&gt;UIBackgroundModes&lt;/key&gt;
      &lt;array&gt;
          &lt;string&gt;bluetooth-central&lt;/string&gt;
          &lt;string&gt;bluetooth-peripheral&lt;/string&gt;
      &lt;/array&gt;
  </code></pre>
  
  <p>I created central manager object for scanning in HomeViewController : </p>
  
  <pre><code>   let centralManager = CBCentralManager(delegate: self, queue: nil)
     centralManager.delegate = self
     let options  = [CBCentralManagerScanOptionAllowDuplicatesKey : true]
     centralManager.scanForPeripherals(withServices:nil, options: options)
  </code></pre>
  
  <p>I tried scanForPeripherals with services when app in background but it doesn't work :</p>
  
  <pre><code> let backgroundScanOptions  = [CBCentralManagerScanOptionSolicitedServiceUUIDsKey : true]
   centralManager.scanForPeripherals(withServices: [customServiceUUIDs], options: backgroundScanOptions)
  </code></pre>
  
  <p>What can I do for re-connect device in background ?</p>