QuizUp - QuizUp gives you the opportunity to test your trivia skills against friends and strangers throughout the world.

RafflePress - RafflePress is the best WordPress contest and giveaway plugin. Grow your email list, followers, and website traffic with viral giveaways in WordPress.

A Google a Day - Online trivia game where you use Google's search to answer questions as fast as you can.

UpViral - Referral marketing platform enables anyone in running effective and profitable viral marketing campaigns – in minutes.

Trivia Crack Kingdoms - The amazing quiz game that lets you test your knowledge and challenge your friends to see who is the smartest. Developed by Etermax

Tremendous - Tremendous is a customer and employee loyalty platform that allows companies to reward their customers for surveys promotions and referrals.