Let's be honest: many of us go into startups to be cool. The common answer of being 'passionate' (about startups/entrepreneurship/tech) often comes after gaining some expertise and leveraging it to create social impact.
Dude, how did you build up your programming skills enough to launch an app at 20-22 yrs old? It says on wikipedia you graduated with a degree in Physics and Philosophy. I'm guessing hacking was a hobby built up from your early teens?