This document summarizes Davide Di Cillo's presentation on making a business from iPhone applications. It provides statistics on the size of the iPhone app market with 25 million users, 30,000 apps, and 500 million downloads. It discusses that being successful is not easy and requires finding a need, researching competition, considering budgets, choosing a business model like selling apps, using advertising, or indirect models, and marketing apps through press and social media rather than relying on the app store. The document wraps up by suggesting using smaller apps to fund larger, more complex apps.