Social Locker is a WP plugin that locks your most valuable site content behind a set of social buttons until the visitor likes, shares, +1s or tweets your page. It helps to improve social performance of your website, get more likes/shares, build quality followers and attract more traffic from social networks.

Demo:

https://tinyurls.ca/HYdKL

https://www58.zippyshare.com/v/sICimOXk/file.html

https://mega.nz/#!am5QWIyL!NFvWvHI_3Kz6L9ua1sKWJ02JX4GbG22vf-wgw3Kwx_g

http://uploadseed.com/KU