Belgian train schedules incl. delays are announced in real-time on this website:
[url removed, login to view] (dutch/french only but the point is clear: enter a station name + time and you receive all information on departing / arriving trains. try out with for example 'brussel-centraal').
I would like to turn this into a very simple iPhone application. The toughest part will be to build (or use) an invisible scraping layer to obtain the data (indeed, government doesn't have a public API!!). You should make a trade-off between scraping the whole website every 5 mins and letting the app work on your own database (ideal for large user base) or querying the website per iphone request (better for small populations, resulting in closer to real-time information but maybe slower app behavior?).
I would like to receive a request for quotation for this project as I have a client who is interested in distributing this service commercially. If you have some references feel free to let me know as well.
Some work from guys who made a trial version of the service (excl. the scraping I think):
[url removed, login to view] (incl. screenshot) and [url removed, login to view]
Thanks in advance. Do not hesitate to contact me for questions.