How to bring up number pad on mobile devices in Matrix Table - Text Entry Table

Hi community,
I have a matrix table with short text entry boxes. Depending on the previous answers in the survey these will be around 3-6 rows and 2-3 columns, so up to 18 boxes. I want respondents to fill these with a one-digit number each (1-7). To facilitate this, I'd like to force the number pad to come up on mobile devices. For other question types I was able to do that by adding this to the JS on ready:
jQuery("#"+this.questionId+" .InputText").attr('type', 'tel');

Unfortunately, this approach is not working for this matrix table question. Any idea what I can do to fix this?
Any help is greatly appreciated.

Thank you very much!