For reasons I can't remember, I focused on the games category. The result was a list of 16 potential games that I could program. I downloaded all the games to get an idea of how much they could be improved upon and how hard they would be to develop. I then made a manual color-based ranking of the games and decided on creating a solitaire game. Not because it was the easiest to make or made the most money, but it seemed to have the right combination of criteria. I'd be able to make it during weekends, I was pretty sure people would pay for it, and I felt confident that I would be able to make a better version. On top of that, there seemed to be several different versions of solitaire, which meant that I could re-use a lot of my code-base if I decided to make the other versions as well.