As far as I know, in the world of PhoneGap there is no way to do this. You can view the available keyboards here . You could probably roll your own if you can in objective-C, but then you will have to create a plugin for it so PhoneGap can see it.
One of the keypads not shown on this page is UIKeyboardTypeDecimalPad, which is a telephone keypad with numbers and decimal point, which can also work for your application. Shown here:

However, I was not able to figure out how to show this via HTML.
If you want to use the phone keypad, you must use:
<input type="tel">
, , :
<input type="number">
( -, , , ), UIKeyboardTypeDecimalPad, :
<input type="decimalNumber">