AddThis - AddThis free website tools include share buttons, targeting tools and content recommendations help you get more likes, shares and followers and keep them coming back.

Referral Candy - Run a fully automated, customizable and easy to integrate referral program for ecommerce.

Shareaholic - Shareaholic is trusted by over 300000 brands, businesses, agencies, and individuals to grow website traffic and engagement 24 hours a day, 7 days a week.

Viral Loops - Viral Loops is a viral and referral marketing platform to launch ranking competitions, sweepstakes, pre-launch and referral programs.

AddToAny - Share buttons by AddToAny, the universal sharing platform for websites and apps.

Firewards - Setup a referral and rewards program for your email list or newsletter.