IOS 13 and how to install fonts and applies

Since it is possible IOS13, to install custom fonts and use, as follows:

The Fonts tab is located under Settings -> Generally -> Fonts

First you install the app Font Diner:

After installation, we open the app and switch to the tab Library and activates the fonts

Now we find the fonts also under Settings -> Generally -> Fonts.

Unfortunately, the fonts can not be applied system-wide. With today's update of Pages and Keynote, the fonts can be selected in the application.