Re: Font size: "How can I adjust this other than the text size slider in settings, which has no effect on this?
This affects a number of apps and my top news widget which shows 2 lines of text in that very small space that I have to scrunch to read. Also the headers in WhatsApp are super tiny. I can barely see the “online” below the persons name.
The text size slider only affects content that is displayed after I enter into an article, for example. It doesn’t change the header sizes."
See how to: Zoom in on the iPhone screen - Apple Support
Eg: says:
"In many apps, you can zoom in or out on specific items. For example, you can double-tap or pinch to look closer in Photos or expand webpage columns in Safari. You can also use the Zoom feature to magnify the screen no matter what you’re doing. You can magnify the entire screen (Full Screen Zoom) or magnify only part of the screen with a resizable lens (Window Zoom)."
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For specific apps : See: Customize visual accessibility settings for specific apps on iPhone - Apple Support
Eg: says:
"You can choose different color, text size, and motion settings for certain apps or for the Home Screen and App Library.
- Go to Settings
> Accessibility > Per-App Settings. - Tap Add App, then choose an app from the list (or Home Screen & App Library).
- Tap the name of the app (or Home Screen & App Library) to access its settings."