The last app I worked on before focusing on the Android Developer Challenge II was PetBook, a little app that let's you store information such as groomer and vet info about any number of pets, and create photo albums for each pet. There's an analogous app for the iPhone, and I since DogWhistle had done so well, I thought this would be a popular app. I was wrong. The app has had 25 downloads, with 17 active installs. That's a flop.
Things got a bit worse. I'd tried to drop the price from $2.99 to $1.99 several times, but for some reason the price was not updating properly. So I thought I would toggle from free back to paid. Big mistake...that isn't allowed. If you change a paid app to free in the market, you absolutely cannot change it back to paid. I'm not sure why the market is built this way, but oh well. So I had to unpublish that version, change the package name, recompile the app, and resubmit it to get it back on the market in a paid version. Lame.
Recently this site posted a positive review of the app, but it certainly hasn't led to any sales. I'm tempted to just make it free so that people can use it. I worked pretty hard on that app and learned quite a few new things, such as using XML for persistence in Android and how to handle images and image galleries. I think it's one of my best apps and I hate to see it lay there unused.