title: Group VOIP calling in Android
body: <p>What's up guys! Haven't asked a question on SO in a while and I feel a bit out of touch, haha. Anyways, I've recently discovered the wonderful world of voice call over the web using <a href="https://en.wikipedia.org/wiki/Voice_over_IP" rel="nofollow">VOIP</a> and <a href="https://en.wikipedia.org/wiki/WebRTC" rel="nofollow">WebRTC</a></p>
  
  <p>I'm doing some R&amp;D for an idea that I have, and I basically would love the answer to the following questions, by someone who has extensive knowledge in this area and/or has worked on applications that uses this feature over the years. I'll try to keep them simple</p>
  
  <p>1) What are the main differences between VOIP and WebRTC?</p>
  
  <p>2) Which is better suited for a mobile app?</p>
  
  <p>3) Is it possible to achieve a group or "conference" like session where more than 2 people are on an audio call?</p>
  
  <p>4) I've also discovered that Android has built in APIs for <a href="https://developer.android.com/guide/topics/connectivity/sip.html" rel="nofollow">SIP</a>, or <a href="https://en.wikipedia.org/wiki/Session_Initiation_Protocol" rel="nofollow">Session Initiation Protocols</a>, but I've read conflicting blogs about their usefulness. Namely there is a lack of support for many modern codecs, etc. I'm not too familiar with this either so any clarification or insight on this would be helpful as well!</p>
  
  <p>5) What are some of the best or most popular libraries for working with this kind of stuff?</p>
  
  <p>Again, completely new to this stuff but find it very exciting. Any help from an experienced person in this area would be greatly appreciated. Thank you!</p>