I have an app which runs excellently on an iPhone 4, and comfortably on a 3GS. Is it possible to target only the 3GS/4 and not the 3G? The 3G just freaks out when I run it, all sorts of graphical glitches, crashing, low fps etc, I don't even want 3G users to see the app on the store. I can't really 'tone down' the app to use less memory/power for the 3G, it would remove the main purpose of the app.
The only way I have come up with is to adding multitasking as a requirement for the app in the info.plist, but this seems a little hacky.
Also, is this likely to get me in trouble as far as submission goes?