This is only a startup in the loosest sense, but after I left Naughty America the first thing I did while looking around for client work was build an iPhone app

This is only a startup in the loosest sense, but after I left Naughty America the first thing I did while looking around for client work was build an iPhone app for managing Shopify stores. It was the first one to hit the App Store, and I had some nice conversations with Tobias Lutke of Shopify. He hooked me up with a New York Times interview, promoted the app on the Shopify blog, and there was even talk of buying the app from me. It was very, very basic, so I held out with the intention of fleshing out the feature set before considering selling it. Six months went by, and I always seemed to find things to work on besides the app. Tobias even gave me a heads up about a competitor hitting the App Store. A few months after that, I found out that Shopify bought the competitor app for a pretty decent sum of money and made it official and free. Had I worked on updates for my Shopify app instead of taking on the (fairly low-paying) clients I did, I probably would have made much more in sales than I did with client work, not to mention whatever price I could possibly have gotten from selling the app. From the whole experience, I learned to manage my time, money, priorities, and client base in a way that allows me to give a lot more time to my own projects.