Web publishers and content creators are experimenting with a “cash-less” payment model where people can use social networks to pay for premium products like ebooks, songs, discount coupons, research reports, etc.
Say you have written a short ebook on a particular topic. Now instead of asking 99¢ for a copy, you can let anyone download your ebook either in exchange of a tweet, a like on Facebook or a +1 on Google Plus. The buyer makes a public recommendation of your product on a social network and you reward them with a free copy.
Before getting into the implementation, click here for a demo (screenshot). You can perform a Like, do a +1 or post a tweet and that action will unlock the link to download a PDF file.

Unlock Premium Content with a Tweet, Like or +1

To integrate social payments into your website, copy everything between the <body> tags from the snippet below and add it your website template.  Also modify the line blocks 13 (file URL), 56 (text of the tweet), 61 (URL to +1) & 65 (your Facebook Page).

  1.   <html xmlns:fb="http://ogp.me/ns/fb#">

  2.     <head>

  3.         <title>Pay with a Tweet, Facebook Like or Google +1</title>

  4.         /*  Social Payments by Digital Inspiration (2013)       */

  5.         /*  You are free to use, modify or republish this code  */

  6.     </head>

  7.     <body>

  8.     <div id="fb-root"></div>

  9.     <script type="text/javascript">

  10.  

  11.         function labnol() {

  12.           // The file URL that visitors can download after their Like/tweet/+1

  13.           var url = "http://www.labnol.org/";  

  14.           url = "<a href='" + url + "'>Click here</a> to download the file.";

  15.           document.getElementById("restricted").innerHTML = url;

  16.         }

  17.  

  18.         window.fbAsyncInit = function() {

  19.           FB.init({ status : true, cookie : true, xfbml  : true });

  20.           FB.Event.subscribe('edge.create', function(response) { labnol(); });

  21.         };

  22.  

  23.         (function(d, s, id) {

  24.           var js, fjs = d.getElementsByTagName(s)[0];

  25.           if (d.getElementById(id)) return;

  26.           js = d.createElement(s); js.id = id;

  27.           js.src = "//connect.facebook.net/en_US/all.js";

  28.           fjs.parentNode.insertBefore(js, fjs);

  29.         }(document, 'script', 'facebook-jssdk'));

  30.  

  31.         window.twttr = (function (d,s,id) {

  32.           var t, js, fjs = d.getElementsByTagName(s)[0];

  33.           if (d.getElementById(id)) return; js=d.createElement(s); js.id=id;

  34.           js.src="//platform.twitter.com/widgets.js"; 

  35.           fjs.parentNode.insertBefore(js, fjs);

  36.           return window.twttr || (t = { _e: [], ready: function(f){ t._e.push(f) } });

  37.         }(document, "script", "twitter-wjs"));

  38.  

  39.         twttr.ready(function (twttr) {

  40.           twttr.events.bind('tweet', function(event) {

  41.             labnol();

  42.           });

  43.         });

  44.  

  45.         (function() {

  46.           var po = document.createElement('script'); 

  47.           po.type = 'text/javascript'; po.async = true;

  48.           po.src = 'https://apis.google.com/js/plusone.js';

  49.           var s = document.getElementsByTagName('script')[0]; 

  50.           s.parentNode.insertBefore(po, s);

  51.         })();

  52.     </script>

  53.  

  54.      <div id="restricted">

  55.  

  56.       // Add the default text of the tweet and your Twitter handle    

  57.       <a href="https://twitter.com/share"                                       

  58.           data-text="Digital Inspiration is my favorite how-to blog http://labnol.org" 

  59.           data-via="labnol" class="twitter-share-button" data-lang="en"></a>

  60.  

  61.       // The URL of the page that visitor need to +1 on Google Plus

  62.       <g:plusone size="medium" callback="labnol"

  63.           href="http://www.labnol.org/"></g:plusone>

  64.  

  65.       // The full URL of your Facebook Page goes here

  66.       <fb:like href="http://www.facebook.com/digital.inspiration" send="false" 

  67.           layout="button_count" width="220" show_faces="false"></fb:like>

  68.  

  69.      </div>

  70.     </body>

  71.   </html>


Here’s how the code works:
When the user clicks on any of the social buttons, the event is captured and then, using simple JavaScript, the link to download the file is added in place of the button. If the user open the tweet dialog but decides not to post one, that “cancel” action won’t unlock the secret link.
There are ready made solutions available, Pay with a Tweet is a popular one, but they require too many steps for the user to complete the transaction. Here, it’s as easy as clicking the regular “tweet” or “like” button.
Also, anyone with technical skills can easily discover the download link from your HTML source code but most web users aren’t likely to do that.