Spotify Apps Api - Tabs

index.html

<script type="text/javascript">
function init() {
   console.log("init()");
   sp = getSpotifyApi(1);
   // detects arguments value for tab  
   sp.core.addEventListener("argumentsChanged", function (event) {	
      console.log('args changed', sp.core.getArguments());			
   });
}
</script>

manifest.json

{
    "DefaultTabs": [
        {
            "arguments": "tab1",
            "title": {
                "en": "title tab 1"
            }
        },
        {
            "arguments": "tab2",
            "title": {
                "en": "title tab 2"
            }
        }
    ]
}

Thanks man. :)