That's correct - we have the aforementioned code in the OnGetCellEditorProperties event, but when tapping on a field in the grid, the iPad shows the full keyboard. I have assembled a small demo project that demonstrates this issue - is there some way I can send that to you for testing?
This issue may not be a TMS issue - I get the same behaviour if I add a regular TEdit to a form, then set the KeyboardType to "NumberPad" in the IDE. Result: iPad Air iOS 9.2 still shows the full keyboard - I will do some additional research on Delphi forums.
When setting it to NumberPad, we get the keyboard which has numbers at the top. It's not the numbers-only keyboard. I think the implementation in FireMonkey is for iPhone only.