title: Get receiver's phone number for android app referral via whatsapp
body: <p>In my android app I want user to send app link via whatsapp to his friends. I was able to send message but I have to store receiver's phone number too so that if his friend(receiver) installs the app the sender will be rewarded. 
  Here is my code for sending whatsapp message :</p>
  
  <pre><code>    Intent waIntent = new Intent(Intent.ACTION_SEND);
      waIntent.setType("text/plain");
              String text = "link to app";
      waIntent.setPackage("com.whatsapp");
      if (waIntent != null) {
          //waIntent.
          waIntent.putExtra(Intent.EXTRA_TEXT, text);//
          startActivity(Intent.createChooser(waIntent, "Share with"));
      } else {
          Toast.makeText(this, "WhatsApp not Installed", Toast.LENGTH_SHORT)
                  .show();
      }
  </code></pre>
  
  <p>When user is done with sending the message, I want to store the receiver's phone number. What should I do for that?
  Also if there is any other way of doing referral via whatsapp then do tell.</p>