There's also some information in the graphic about the in-app purchases on the freemium app. According to NimbleBit, over 12 million potions and over 4 million in-game stamps have been sold to players. Prices on those actually vary depending on how many you buy at a time -- you can buy 10 for 99 cents, or 1000 for $29.99. But we've already heard that most of the purchases are of the 99 cent variety, so when you put the average closer to that, I calculate the app has made well over a million dollars. That's before Apple's cut, of course.
How'd they do it? The graphic also points out that the average time inbetween game updates has been only around 11 days. Since release, NimbleBit has added some very significant features to the game, including a new mode to race frogs, new goals to hit while breeding them, and a social feature to share which frogs you're working on. Turns out the freemium model, combined with constant attention and improvement from a core team of devs, translates into player interest -- and profits.