When George, Scott, and I graduated from Oberlin College in 2008, we didn't want to get jobs, so we started a startup. Skritter is a web/iOS/Android application for learning Chinese and Japanese characters. Despite our potentially misguided focus on learning power over mass appeal--who wants to actually learn to write 10,000 words these days?--it has done well so far, and we are free.
Skritterers have studied about 620,000,000 items. Whoa. It's a strange feeling to have taught people many thousands of times more characters than I myself know.
When you do a small startup with your two best friends, there's a ton of stuff to do, and you do a lot of all of it. With Skritter, in addition to a lot of everything, I did thousands of hours of developing: back-end with Python, Django, and Google App Engine; front-end with Flash, jQuery, and Sass; and mobile with iOS. The iOS app came last, so it's the best.