Detect mobile device in PHP

function isMobile()
		{
			return preg_match("/(android|avantgo|blackberry|bolt|boost|cricket|docomo|fone|hiptop|mini|mobi|palm|phone|pie|tablet|up\.browser|up\.link|webos|wos)/i", $_SERVER["HTTP_USER_AGENT"]);
		}
if(isMobile()){
echo "it is mobile device";
}

facebook , Twitter and G+ , Pinterest share button code

Facebook
<br>
<div style="width:300px; border:solid 1px;">
				<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=v2.4";
				  fjs.parentNode.insertBefore(js, fjs);
				}(document, 'script', 'facebook-jssdk'));</script>
				<div class="fb-share-button" data-href="<?php the_permalink();?>" data-layout="button_count"></div> 

Google plus
<br>
				<a href="https://plus.google.com/share?url=<?php the_permalink();?>" onclick="javascript:window.open(this.href,
  '', 'menubar=no,toolbar=no,resizable=yes,scrollbars=yes,height=600,width=600');return false;">
  <img
  src="https://www.gstatic.com/images/icons/gplus-16.png" alt="Share on Google+"/></a>


Twitter
<br>

<a href="https://twitter.com/share" class="twitter-share-button" >Tweet</a>
<script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+'://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js,fjs);}}(document, 'script', 'twitter-wjs');</script>
				</div>


Pinterest
<br>

<a href="http://pinterest.com/pin/create/button/?url={URI-encoded URL of the page to pin}&media={URI-encoded URL of the image to pin}&description={optional URI-encoded description}" class="pin-it-button" count-layout="horizontal">
    <img border="0" src="//assets.pinterest.com/images/PinExt.png" title="Pin It" />
</a>