If you have any web views in your app (Terms and Conditions and Privacy Policy, I'm looking at you), you can also support Dynamic Type for them. You can set an Apple system font with the same styles available for native development in your CSS.

Two examples of a web view. One with the default text size and another one much bigger with the AX5 Dynamic Type. To achieve that, you can define the font in the css. Some examples are: -apple-system-body,  -apple-system-headline -apple-system-footnote...