>>> Create free Android apps to spread reading, writing, and arithmetic skills, and prove their effectiveness over an 18-month period in African pilot communit

>>> Create free Android apps to spread reading, writing, and arithmetic skills, and prove their effectiveness over an 18-month period in African pilot communities. 5 prizes of $1M and a grand prize of $10M. That seems quite viable for the HN crowd. However, this is rather subjective compared to other problems. Many other problems are more like true/false. Still, that's quite interesting and an app, designed for learning, with heavy optimizations on UX seems like a very commercially viable product. Given you have to do the skills of enterprise sales :)