<i>&quot;regional&quot; services simillar to WhatsApp</i><p>The app with a billion plus installs, quite likely the largest actively used chat app in the world is a &quot;regional&quot; service. Just to take a wild guess, you&#x27;re not an iOS user from the bay area by any chance? 
 I haven&#x27;t come across too many Android users who are <i>not</i> using WhatsApp in the US.