I wrote a webapp! It is designed to solve one problem: help you keep track of your weight. I had iphones and nexuses in mind, so it should work well on those.
Please check it out: http://poundometer.appspot.com/
Nerd Fanboy Talk:
I love AppEngine. I don't know of other technology that lets you go from something in your head to a production deployed app in a few minutes; where you don't have to worry about creating tables, dealing with databases, all that nasty stuff. And running your own servers too.
OK, I lied. I am aware it is possible to do these things running my own python/django instance or having someone host it or doing something similar with ruby/rails and a myriad of hosting services. Regardless, I stand by my adulation of AppEngine. The ability to write something and deploy it in minutes/hours is simply awesome.
Edit:
Forgot the best bit: Throwing in an easter egg that triggers if user=.
Result (via twitter):
"oh and the bf made me a valentines day app (sort of)! Doesn't get any sweeter than that. ;)"
Nerd Stats:
find . | xargs wc -l
total: 236
python, appengine, Google Chart APIs.
Seashore to do simple image and favicon.
~3 hours, including an inordinately long time dealing with css and figuring out that stupid meta viewport tag to make it look right on a handheld.