Facebook app:- I want to keep off my chat but still want to check who else is online.

This is simple require online_presence permmision to fetch the list of your online friend. There is not need to turn your chat on.

Run locally

Configure Apache with a VirtualHost that points to the location of this code checkout on your system.

Create an app on Facebook and set the Website URL to your local VirtualHost.

Copy the App ID and Secret from the Facebook app settings page into your VirtualHost config, something like:

<VirtualHost *:80>
    DocumentRoot /Users/adam/Sites/myapp
    ServerName myapp.localhost
    SetEnv FACEBOOK_APP_ID 12345
    SetEnv FACEBOOK_SECRET abcde
</VirtualHost>

Restart Apache, and you should be able to visit your app at its local URL.

[Demo] (https://apps.facebook.com/336197989828137/)