Implemented by someone a way to change the text that is used in iOS (iOS Settings - text size)

Hello!

Tell me, did someone implement the method of changing the text that is used in iOS (iOS Settings - text size) Is it a slider with intermediate scaling points?

Can anyone have an example when the visual part and the working algorithm?

Thanks!
Implemented by someone a way to change the text that is used in iOS (iOS Settings - text size)
 
 
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