This rocks. Thanks for sharing all the details.

I was a little mislead by the title being "the average person donated 7.66$" rather than "of people who donated, the average donation was $7.66," i.e. the average user did not actually donate money. Nevertheless, this was a high price to pay in a day and age when people avoid paying $0.99 for the most entertaining and useful apps.

I have not yet downloaded the app (I am about to), but I am very appreciative of the decision to not put ads in the app. I am a strong believer that the ad-supported model must be broken, and I believe the way this will happen will be via true usefulness and content depth (with which money can come from in-app purchases, etc.).