Tony Wright investigates the economics of paid apps vs in-app purchases, and finds that IAPs are where the money is.
So why are free apps outperforming paid apps? That deserves its own post. In brief, it comes down to ARPU (average revenue per user). Farmville-style games can pull in an ARPU $5 or more per month. In fact, there are reports of $13 ARPUs. Per month! Per user! Average!
How is this possible? Virtual goods elegantly fill up the demand curve for an offering. In other words, they accommodate customers who can happily spend hundreds or thousands of dollars (“Whales”, in Vegas parlance) without having to give up mainstream users (who can still be valuable as evangelists beyond the fact that they give the whales someone to play with).
This shouldn't be a huge surprise. After all, there's a good reason why SaaS is such a popular business model: a low monthly price tends to generate more revenue than a higher up-front price (for most types of products). IAP's throw in the advantages of an app-store like model where people can keep buying more without entering their credit card details.
In conclusion: if you can make your app charge via IAPs (but that's not always possible or advisable), do so, because it will make a significant difference to your revenues. In particular, as Tony suggests, try to ensure that if a customer turns up who, for whatever reason, feels like blowing $500 on your app, give them a way to do so.
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