For hosting common files it's ok. Also it is on Android too do, great to transfer files between your Windows and your phone. But if you want better security you have to subscribe a monthly offer.
Trivia Crack - Produced by Etermax, Trivia Crack lets players answer trivia questions and compete against other people on mobile devices.
Dropbox - Online Sync and File Sharing
QuizClash - In QuizClash, you can challenge your friends or random opponents to a game of trivia.
Google Drive - Access and sync your files anywhere
QuizUp - QuizUp gives you the opportunity to test your trivia skills against friends and strangers throughout the world.
Mega - Secure File Storage and collaboration