I believe that market is validated and quite big. Idea is nothing new. Some of competors are everyone from iTunes, Netflix, Amazon Video, down to sites like Railstutorials.org...

I am struggling to find my initial place in this wide market. Where should i focus - Education? Movies? Sports? I got some good feedback and contacts in all these niches and dont know where should i focus my efforts.

I got two real(not counting number of test) purchases(i suspect from friends of my customer).