Does apple allow any customized keyboards?

I'm sorry if this is a "duh" question, but this 开发者_开发百科is sort of compounded with this. I've figured out that I need a custom view that basically mimics the virtual keyboard on the iPad, but with a different set of keys (like both numbers and letters). Here's the issue: this app is something that will be sold, so what I'm wondering is whether Apple allows custom keyboards that just mimic the regular keyboard.

Absolutely. As of iOS 4, you can set the inputView property of any UIResponder (like a UITextField) to your own custom view, and the system will display that view at the bottom of the screen in place of the system keyboard whenever that view gets first-responder status.