Does your idea have potential to be a sustainable business? Paid apps and in-app-purchases can still work well. There are a number of developers who make a living that way. Hours, for example, did really well as a $5-10 app. But at the end of the day, the simple pay-per-download model can have limited potential and it is important to consider if there are other more creative business models for your app, even if you start with pay-per-download.

Is your app a good business model? The experts have to think about this too.