I use The Bible Study App on my iPad Mini every Sunday to look up the text my pastor is preaching from and to take notes on his message. Since the iPad mini has a smaller screen, being able to enlarge the font, not just on the viewable text but also my notes comes in very handy.
Here’s how to do it:

Tap the ‘Settings’ icon and then tap ‘Advanced Settings’.
Now tap ‘Advanced Font Settings’ and you’ll see a variety of options for changing the fonts for the App. Scroll to the bottom and you’ll see two options that relate to your notes.

Notes Font Size

Select the desired font type and size that looks best on your iOS based tablet or phone and you’re good to go.

Notes Font Size1