iOS 17 lets you change system text size globally and, through Control Center, adjust text size for supported individual apps.
Steps
- Open Settings > Display & Brightness > Text Size.
- Drag the slider until ordinary interface text is comfortable.
- For larger accessibility sizes, open Settings > Accessibility > Display & Text Size > Larger Text and enable Larger Accessibility Sizes if needed.
- To vary size by app, add Text Size to Control Center, open the target app, then use the Text Size control and choose the app-only scope where available.
- Check several apps because not every app respects Dynamic Type equally.
How it works
Dynamic Type allows compatible apps to scale text while preserving layout. Display Zoom is a different feature that enlarges more of the interface, not just text.
Important considerations
iOS 17 is an older release in 2026. If the iPhone supports a newer security-supported iOS version, update it; menu names can change slightly.
Practical guidance
Bold Text, Increase Contrast, and Display Zoom can improve readability in ways that font size alone does not. Larger accessibility sizes can cause controls to reflow, so test frequently used apps. If an app ignores Dynamic Type, look for its own text-size setting before assuming iOS failed.
Additional details
Text Size in Control Center can be especially useful when one app needs larger text but another already looks oversized. The app-only selector appears at the bottom of the control on supported versions. Reset to the default if buttons or labels become clipped, then try Display Zoom or the app’s own accessibility options.
Kermit Matthews is a freelance writer based in Philadelphia, Pennsylvania with more than a decade of experience writing technology guides. He has a Bachelor’s and Master’s degree in Computer Science and has spent much of his professional career in IT management.
He specializes in writing content about iPhones, Android devices, Microsoft Office, and many other popular applications and devices.