gistfile1.js

// the UUID of your pebble app
var uuid = '39457783-362f-4343-8846-7fec4fc6268f';

document.addEventListener('deviceready', function(){
    Pebble.registerReceivedDataHandler(uuid, function(err, info){
        if (err) return console.error(err);
        navigator.notification.beep(1);
    });
});