Connect web and mobile api with socket using node.js - node.js

Question

I'm new in node and socket programming.
In my project Requirement is like this,
One Server which house the set of questions and set of campaigns. campaigns contains questions. And admin will start or stop campaign.
Once Campaign start, Front end of Web Application will display only questions and mobile application display Answer of question and question will automatic reload after every X second in both web and mobile app.
I tried web socket and socket.io this is working fine for web application requirement. But I don't know what for mobile API.
Below is the code for socket.io.
server.js
var mysql = require('mysql');
// Let’s make node/socketio listen on port 3000
var io = require('socket.io').listen(3000);
// Define our db credentials
var db = mysql.createConnection({
host: 'localhost',
user: 'root',
password: '****',
database: 'database_name'
});
// Log any errors connected to the db
db.connect(function (err) {
if (err)
console.log(err);
});
// Define/initialize our global vars
var questions = [];
var total_question = 0;
var isInitNotes = false;
var count = 0;
var sql = "";
// call once per connection, create new connection
io.sockets.on('connection', function (socket) {
console.log((new Date()) + ' Connection from origin ' + socket.handshake.headers.origin);
//io.sockets.emit('users connected', socketCount)
socket.on('disconnect', function () {
console.log((new Date()) + ' Disconnected from origin ' + socket.handshake.headers.origin);
});
db.query('SELECT COUNT(vQuestion) as total_question FROM questions')
.on('result', function (data) {
// Push results onto the questions array
total_question = data.total_question;
});
// select questions from DB
var questionInterval = setInterval(function () {
// check condition for question is over or not
if (count < total_question) {
sql = 'SELECT vQuestion FROM questions LIMIT ' + count + ',1';
console.log(sql);
db.query(sql)
.on('result', function (data) {
// Push results onto the questions array
questions.pop();
questions.push(data);
})
.on('end', function () {
// Only emit questions after query has been completed
socket.emit('get questions', questions);
});
count++;
} else {
clearInterval(questionInterval);
}
}, 5000);
isInitNotes = true;
});
Index.html
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<script src="http://localhost:3000/socket.io/socket.io.js"></script>
<script>
$(document).ready(function(){
// Connect to our node/websockets server
var socket = io.connect('http://localhost:3000');
// Initial set of questions, loop through and add to list
socket.on('get questions', function(data){
var html = ''
for (var i = 0; i < data.length; i++){
// We store html as a var then add to DOM after for efficiency
html += '<li>' + data[i].vQuestion + '</li>'
}
$('#questions').append(html)
})
})
</script>
<ul id="questions"></ul>
<div id="usersConnected"></div>
Commands for server
node server.js
Fri Oct 21 2016 10:30:35 GMT+0530 (IST) Connection from origin http://localhost
Web browser (Web Application)
http://localhost//index.html
display a question every 5 seconds.
In my case, Only one web Application will be there but, More than one mobile users will connect at same time.