iA Writer - Minimal Design, Maximum Focus
QuizUp - QuizUp gives you the opportunity to test your trivia skills against friends and strangers throughout the world.
MacDown - MacDown is an open source Markdown editor for OS X, released under the MIT License.
Buzz! The Big Quiz - Buzz! The Big Quiz is a Trivia, Party, Single and Multiplayer video game developed by Relentless Software and published by Sony Computer Entertainment.
MWeb - Pro Markdown writing, note taking and static blog generator
Trivia Crack - Produced by Etermax, Trivia Crack lets players answer trivia questions and compete against other people on mobile devices.