Numeric Keypads

I'm starting work on another app, but I need a means of entering currency values (Let the user enter $2.00, for example). 

There's three numeric keypads available on the iPhone. Let's have a look and see how well they suit out needs.

First up is the standard iPhone keypad. Looks nice, large keys, but as far as I'm aware, this isn't available to me as a developer. It's also got the letters under the numbers, which is not too much of a problem, but is extra noise, has extra symbols we don't need (*, #, +) and has no means of entering a decimal.

Second up, we have the second page of the standard text editing keypad. I've discounted this almost immediately as the numbers are too small and there's too many extra characters we don't need.

Next.

Finally something that looks promising. Except it doesn't when we look closer. Sure it has nice big buttons and it's available for use, but we still have no decimal. There's also no clear way to signal when you're done entering the value.

So, I thought it would be a fun exercise to build my own.