This is an excellent series by Stuart Hall: he developed a 7 minute workout app, and he’s been posting details, numbers, and comments on what it’s like to enter the App Store market today.

Particularly interesting is the switch to a free model with In-App Purchase, detailed in part two:

How does In App Purchase (IAP) stack up against a paid download? For this app it’s been an increase of over 3x from around $22 per day to around $65 per day. The IAP converts at approximate 2-3% of the downloads per day.

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IAP increases revenues – For better or worse for the ecosystem as a whole, it’s been proven over and over again it makes more money.

While Stuart’s story won’t apply to every kind of app category and pricing scheme, there are several data points and charts worth considering. Make sure to check out part one and part two — I hope there will be a part three as well.