The iPhone and Android have been out for ages, and I've meant to put together apps (even going as far as getting a Mac to do the development work for iOS, but haven't up to now had the time or a decent project to undertake.
However finally I've managed to put an app together and it was submitted and is now in the app store and android market place. The app, for a cumbrian car dealership, is a JSON powered search which queries a database and brings back the search results. The app features a map, a couple of buttons for emailing or calling the dealership and multiple images for each vehicle.
Technology wise I used Appcelerator Titanium for the mobile development with Django and JSON for the database. Future plans involve actually developing directly in both Java and Objective C, but for now and in the time I had available for learning and deployment Titanium was a good choice.
The apps are both available for free: