Can you use the Facebook send button functionality (https://developers.facebook.com/docs/plugins/send-button) without an appid?
The example from the Facebook seems to work without an APP_ID
<body>
<div id="fb-root"></div>
<script>(function(d, s, id) {
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id;
js.src = "//connect.facebook.net/en_GB/sdk.js#xfbml=1&version=v2.0";
fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));</script>
<div class="fb-send" data-href="http://www.bbc.co.uk" data-colorscheme="light"></div>
</body>
but didn't want the button to suddenly stop working if this is required!