Just about every conversation I have with an iPhone developer who's had any level of App Store success eventually (usually sooner rather than later) includes the question, "what worked for you?" I've been trying to distill some kind of pattern -- a sure-fire marketing tactic -- but there are just too many variables.
There are the ones which developers can control (to some extent): the general timing of a release (give or take a month), pricing, quality, external promotion, and certain aspects of the marketing process. There are also variables beyond the developer's control, such as the review process, being featured on an App Store list, the existence and tactics of competitors, duplication and an array of shifting circumstances and bad behavior. What we need is more data, right?
Pinch Media's Jesse Rohland & Greg Yardley, the gracious providers of some great App Store RSS feeds and developers of tools for iPhone app metrics, just published a slideshow (you can see it in the 2nd half of this post) which was presented at the New York iPhone Developers Meetup, sharing analysis of the data and trends they've been observing.
Snazzy charts? Witty banter? Sound advice? Check, check and check. Whether you're curious about the effects of price drops, various usage stats for free versus paid apps or the mathematics of breaking even (maybe turning a profit?), statistical analysis could be your friend. I know, real friends are nicer and more helpful on moving day, but that's what you get for spending all your time writing iPhone applications in dimly-lit rooms. I kid, of course: enjoy the show ...