I've developed an app which sells pretty well all over the world - I can't make a living out of the revenue but I am still happy. The app performs pretty well in most of the (wealthier) countries, but underperforms in the US and Canada. This is where I need the help of the HN community.

=> Why does my app suck on the US market? Is there an obvious reason I don't see?

What I mean by suck on the US market: http://imageshack.us/photo/my-images/585/screenshot20120828at155.png/ The US just makes 2.8% out of my total downloads, although it should be a huge market.

iTunes Link: http://itunes.apple.com/en/app/id473512078?mt=8 Some public analytics: http://www.appannie.com/app/ios/minipedia-offline-encyclopedia-wikipedia-reader

The app has an average rating of 4.25 with 280 reviews worldwide. The average rating in America is 4.0 with 16 ratings. I am using a freemium model and make my profit through in-app sales.

Thanks, Bobby