On the topic of free apps allowing in-app purchases, I noticed recently that I felt trapped by in-app purchases in games I downloaded for my kid. The apps control the screen and seem, at least on apps aimed at kids, to make it intentionally easy to misclick and purchase something, having tiny, well hidden controls to cancel back out or continue without purchasing or upgrading. Since the only hardware button takes me right back to home I feel trapped like I'm browsing the seedier parts of the web with a pre-popup blocker IE. Not really an "Apple" experience.