I just uploaded a new Android app, Shush! Ringer Restorer:
When you turn your ringer off for a movie, this app turns it back on afterwards.
It's activated when you silence your ringer using the volume buttons. You don't need to remember a special app! Once your ringer is off, it asks you how long to stay silent: ½, 1, 2 or 3 hours. Never miss another important call!
I'm familiar with the Android tools, but this is the first app I've written. The whole project took around 16 hours, including downloading the SDK, writing the code, drawing icons, testing, publishing, and open sourcing.
I love Android because it enables apps like this one. My app receives ringer changes, opens dialogs with a polished UI, schedules background tasks, and turns on the ringer. I wrote in on Sunday and my friends downloaded it on Monday. I couldn't do any of this on the other device platforms.
Shush! was a fun project, and I'm now brainstorming a more ambitious follow-up.