TDInputView is an open source replacement for the standard system keyboard in iOS 4.0+. TDInputView subclasses UITextField and replaces the inputView with a custom UIView that you can design. Below is a screenshot of TDInputView in action from my app Wager which can be downloaded from the App Store for free here.
You can download a copy of TDInputView from GitHub here. It’ll be great to hear from you if you do find this useful.