It's very different than your proposed—albeit much better—alternate headline, as revenue isn't the only driver of store rankings. It appears dollars are a very small measurement for general category rankings (there's a different category for "Top Grossing"), since free apps also rank.

Having a headline of "One download was enough to get me to #18 on the app store" is not only clearer, it's also arguably more compelling.

FWIW I thought the article was about how the author reached a top rank by paying someone or investing in ads for 70 cents.