Spend your time/money making an application that isn't so easily duplicated. You said it yourself that you weren't planning to make a mint on this. No point in dealing with the hassle of lawyers, paying the lawyers etc.
If you only had one competitor, it would be possible, but being that you have five competitors, and some of them are free, I'd have to say that the market is saturated and its time to get out anyway.
Sure - He have the submitters story, but he hasn't provided us with evidence beyond a reasonable doubt that Philip has stolen his database.
1. Buy them, right click on both apps in your iTunes Apps list and choose 'Reveal in Finder'.
2. Copy both to your desktop.
3. Rename them to .zip and unzip them
4. Click on the app file and choose 'Show Package Contents'
5. Compare dublinbus.db with dublinbus.png2
They are not totally identical, but there is a very significant overlap that cannot be down to chance.
Also, his e-mail to me admits that he copied my 'layout'.
Though, I agree that his website doesn't him look 'dodgy' by itself.
That wasn't my intention. my intention was that when someone Googles his name they'll get lots of pages saying he's a dodgy person.