HiQ is an Android app that allows you to learn a new language, answer trivia, and math questions directly from your lockscreen. The app allows you to learn a new language(17 total) in under a year. HiQ is trying to increase your iQ by stimulating your brain every time you unlock your phone.
HiQ prompts you with multiple choice question that you need to answer correctly to unlock your phone. You can select the type of question you want answered like math questions, trivia, and language questions. Correct answers are rewarding with coins that can be redeem for more questions, and upgrades. Also the app has Easter eggs to get coins a little faster. The app will track your progress with a history of answered questions.
Check out HiQ HERE