QuizUp - QuizUp gives you the opportunity to test your trivia skills against friends and strangers throughout the world.
Woolah - Knockout Photo challenges with your friends.
A Google a Day - Online trivia game where you use Google's search to answer questions as fast as you can.
SPAR! - Challenge your friends. Put money on the line. Get better.
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
QuizClash - In QuizClash, you can challenge your friends or random opponents to a game of trivia.