MacDown - MacDown is an open source Markdown editor for OS X, released under the MIT License.

Trivia Crack - Produced by Etermax, Trivia Crack lets players answer trivia questions and compete against other people on mobile devices.

Frost - An open API for Blockchain timestamping

QuizClash - In QuizClash, you can challenge your friends or random opponents to a game of trivia.

iA Writer - Minimal Design, Maximum Focus

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