Available in Piebald Basic (Free)
Piebald allows you to customize the size of all text in the app to any size between 5 and 25 pixels, allowing for better resolution on smaller or larger screens.
You can also customize the font family used by the entire interface. Browse and select one of your system’s installed fonts, or pick one of 2,000+ Google Fonts.
To customize the font size and font family, go to Settings → Appearance and change Font Size and Font Family.
Here’s a demo where we change the font size from the default 18px to 15px, and the font family from the default Figtree to Lustria (a Google Font):