Keyboards and Input Views
If appropriate, you can design a custom input view to replace the system-provided onscreen keyboard.
If you provide a custom input view, be sure its function is obvious to people.
You can also provide a custom input accessory view, which is a separate view that appears above the keyboard (or your custom input view).
Use the standard keyboard click sound to provide audible feedback when people tap the custom controls in your input view. To learn how to enable this sound in your code, see the documentation for
playInputClick in UIDevice Class Reference.