Here Social Networks Auto Poster PRO (SNAP PRO) WordPress plugin as Pure PHP API library that automatically post your messages, posts or news to the most popular Social Media Networks like Facebook, Twitter, Google+, Pinterest, LinkedIn, Tumblr, even Blogger/Blogspot.
The first step is Installing the Free Plugin, then activated.
Here the link for download free plugin: http://www.nextscripts.com/files/social-networks-auto-poster-facebook-twitter-g.zip
How to SNAP WordPress to Pro Version? see instruction here:
1. Download “SNAP Pro Upgrade Helper + Serial Numbers” here: Social Networks Auto Poster PRO Multi Account
2. Install and activate “NextScripts: SNAP Pro Upgrade Helper”.
3. Enter the serial numbers that you have downloaded on Plugin settings. Also automatically Installed Multi Account (Pro) plugin upgrade and API Libraries.
4. Finish 
