On Android, it's possible for the user to set a larger font for accessibility reasons.
Discussions like this one go into some details on how/whether the named or fixed (number) sizes are affected by accessibility settings.
I have a slightly different question. Is there a way to adjust the size of controls to account for font size? With our app, if the user sets a large font size under Accessibility, then the text in buttons, Infragistics DataGrids, ListViews etc. don't fit into their controls. Am I missing something?