That would be awesome! I've never done apps before, and the connection to a database - from a device that may not have a stable connection - seems like a challenge as well. I've only done some googling around to figure out how I'd have to do this. I think I can use Zbar's opensource code for the scanner. I'll need to either use my mothers mac laptop, or install osx on a virtual box to get access to the app development software. The actual database isn't really a problem, I just need a list of 1000 entries, with participant names, startnumber and their starting status (Not started, started, dropped out, finished).
The problems, in order, are getting access to iphone app development software, getting Zbar to work, figuring out the database connection (after scanning a number, it should display the participants name and update their status), and building the apps graphical interface.