It seems like Readdle is all over the App Store these days. Calendars, Scanner Pro, and even the now-defunct ReaddleDocs have received plenty of praise (and downloads) over the years - all good indications of a developer that knows what they're doing. The Verge recently went to visit the folks at Readdle, based out of Odessa in the Ukraine, to learn a little more about how they've managed to get to where they are today. And also how they've managed to do it without setting up shop in Silicon Valley.
You should definitely check it out, it's a fascinating read.