title: Use SmartPhone NFC as Access Control identifier
body: <p>We have a rather large management system and are looking to extend it with a door access control system, getting that to Work with some mifare cards is pretty straigtforward.</p>
  
  <p>However alot of smartphones already have an NFC chip that could be read as well and used for identification.</p>
  
  <p>My goal would be that the user should simply be able to open the door with their phone.
  They should not need to turn on their phone, so iam thinking i would need to emulate a passive Card, is this at all possible without the phone being on?</p>
  
  <p>I know android now supports HCE, but is that the right thing to use for this purpose?
  <a href="http://developer.android.com/guide/topics/connectivity/nfc/hce.html" rel="nofollow">http://developer.android.com/guide/topics/connectivity/nfc/hce.html</a></p>
  
  <p>And how would you do this on Windows Phones that also have an NFC chip?</p>