Script for displaying number keyboard in mobile

Is it possible to run a custom script in custom format settings that will display the numerical keypad instead of the alphabetical keyboard when using a form on a mobile device? I am running a custom format script for a time calculation because I need a leading zero, however when the end user clicks on the form it opens up the alphabetical keyboard instead of the number pad. 

I know in the field format settings if I select number format, when the PDF is viewed on a mobile device it will display the numerical keypad, but I am running a custom script in that field so I can't switch it to the number format. I have spent hours and hours searching, and I have found nothing so far. Any help would be greatly appreciated.