title: Syncronize timestamp between devices
body: <p>I'm looking into syncronizing some devices, and I am having a local solution requiring to work without internet. </p>
  
  <p>I have used the System.currentTimeMillis(); but it's good only for one device as system clocks arent totally sync even with automatic time update and same timezones. So I was wondering, what can I use as I cannot use NTP server/internet? </p>
  
  <p>Is the fastest way to get it by setting up a server on a pc, connect via cable to the router and query it for it's timestamp?
  Or use a android device as a server and query that?  </p>
  
  <p>Is there any other solution? open to everything within java/c++ and wlan/wifi (no internet)</p>
  
  <hr>
  
  <p>Update, </p>
  
  <p>Have been searching for some hours.. And found that many(almost everyone) have the same issue without NTP. Giving it more thought, I will just create that server solution on a lan connection and fetch a timestamp.. Still open for ideas though :)</p>