It's now nearly at the end of February and it's abundantly clear that it's really hard to keep shipping apps at the rate of one a month whilst working in the evenings 🙁
Anyway, what I have done this month - which I'm going to claim in a loophole sort of way - is shipped my Weight Tracker Facebook App
The app is very simple; it uses Facebook's Open Graph to record your weight in pounds on the date you specify. I've also added a page where you can retrieve all your entries so you can see the progress of your diet (or not), and use the Google Chart Tools to make a nice graph of the figures.
Why it's a bit of a cheat in the app-per-month stakes is I did most of the work a few weeks ago, but had to wait for Facebook to approve the Open Graph extensions before the world could see the results on my timeline - and of course use the app themselves if they want. After one false start where I hadn't registered the correct icons for the app on the developer website, it went live this week.
The Open Graph development environment was pretty straightforward to both use and setup once I'd read through the documentation. The whole point of the app was really to learn about the capabilities of the platform, but also to make sure I keep sharing information about my ongoing diet!
I also like the way it was pretty easy to add in summary views on the data, so I can see both the latest weight and the lowest weight on my Facebook timeline with very little extra effort.