Getting started with P5JS and tramontana:

• Download tramontana for iOS or Android
• Download the tramontana library for javascript
• Download the p5js library

Load the libraries in your html file:

<!-- import jquery -->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.0/jquery.min.js"></script>
<!-- import p5js -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/0.5.4/p5.min.js"></script>
<!-- import tramontana -->
<script src="tramontana_min.js"></script>

Now you can create a new tramontana object that links to your device.

var device = new tramontana();  

In the setup function you can call the start function of tramontana, that accepts 2 parameters. The first one is the ipAddress of your device (that you can see on your device, and the second is a callback function that is called if the connection succeed or fails. If the error is undefined the connection is successful and you can do a lot of things with tramontana, like for instance trigger the haptic engine of the device.

function setup(){
    createCanvas(600, 600);
    device.start("192.168.1.23",  function(e){
        if(e==undefined){
            //SUCCESS TRAMONTANA CONNECTED
            device.makeVibrate();
        }
    });
}

function draw()
{
    rect(10,10,100,100);
}

You can check more examples here:
tramontana and p5js
tramontana and p5js alternate example