title: Why do whatsapp web application needs phone connection all the time?
body: <p>WhatsApp just announced a new web application <a href="http://blog.whatsapp.com/614/WhatsApp-Web">see here</a>.<br>
  For some reason, the interface requires the phone to be connected all the time. Is it for performance reasons (not to create additional load on their current servers)? Is there any other constraint that cause that?</p>