Is there a way to add text inside of the modal

[lathomas64]

In certain conditions we treat picking the current days date as no date selected which is a valid option and I would like to be able to display a label inside the date modal to say something like: "If a date is not selected, the hold will be frozen until you thaw it."
Is there any way to get this message inside the modal for both android and IOS? I think the custom header option would work for IOS but i need something that would work in both places.