Litnerd - The Pixar for education, reading program for K-5 schools
Daily Curiosity for iOS - The top 5 things to learn on Curiosity.com, delivered daily.
Cotrio - The most beautiful way to move your brain and imagination
Endless - Random and amazing Wikipedia articles.
WonderBox - Wikipedia for kids — Learn with friends and family
Corbie - Expand your general knowledge in just 5 minutes a day