Support the system-wide text size in iOS

[mikix]

Have you read the Longevity Statement? Yes.

Is your feature request related to a problem? Please describe. When I have adjusted the system text size (Text Size in Settings, called the Dynamic Type feature in the dev docs I think: https://developer.apple.com/documentation/uikit/scaling-fonts-automatically ), most apps correctly increase their UI font accordingly.

But Standard Notes does not - it’s fonts remain small.

Describe the solution you'd like Use the appropriate iOS API to dynamically set font size for both UI elements and note text.