Kunal

Sharedom provides the user with responsive sharing buttons for Facebook, Twitter and Google+ (more in later upgrades) that share the current URL. It is really simple and light-weight and comes with a shortcode that can be dropped anywhere to instantly show the sharing buttons.

Sharedom

Responsive sharing buttons for sharing current URL to Facebook, Twitter and Google+

acbaltaci

The simple and 100% working way of google +1 share button. It uses google external api to call. 
Please visit http://www.allthemesnulled.com for demo.

Google Plus Share and +1 Button

This plugin puts a google+ share button on top of posts.

Sharedom vs Google Plus Share and +1 Button