How to Change Text Size for Specific Apps in iOS 15

With the release of iOS 15, Apple introduced the ability to customize text size on a per-app basis rather than forcing a single font scale across the entire operating system. This guide covers the new granular text options added in iOS 15, how the toggle system works, and the step-by-step process for configuring different font sizes for individual applications using the Control Center.

The New Per-App Text Size Controls

Prior to iOS 15, adjusting Dynamic Type in your iPhone settings changed the font size globally across all supported applications and system menus. iOS 15 solved this limitation by introducing a segmented control inside the Control Center's Text Size interface.

When you open the Text Size control in iOS 15 while an app is active, you are presented with two primary options at the bottom of the screen:

  • [App Name] Only: Applies the chosen text scale exclusively to the currently active application.
  • All Apps: Applies the chosen text scale globally across the entire operating system, functioning like the traditional system-wide setting.

This allows you to enlarge text in reading-heavy apps—such as Safari, Mail, or Messages—while keeping a standard or smaller font size for navigation, social feeds, or the Home Screen.

How to Set Up and Use Per-App Text Size

To use the per-app text sizing feature, the Text Size tile must first be enabled in your Control Center.

Step 1: Add Text Size to Control Center

  1. Open the Settings app on your iPhone running iOS 15 or later.
  2. Scroll down and tap Control Center.
  3. Under the More Controls section, find Text Size (represented by an "AA" icon) and tap the green plus (+) button next to it.

Step 2: Adjust Text Size for a Specific App

  1. Launch the app where you want to alter the font size.
  2. Open the Control Center (swipe down from the top-right corner on iPhone X or newer, or swipe up from the bottom of the screen on older models).
  3. Tap the Text Size (AA) control.
  4. Tap the toggle switch at the bottom labeled [Current App] Only.
  5. Drag the vertical slider up or down to choose from the six available Dynamic Type sizes (or more if Larger Accessibility Sizes are enabled).
  6. Tap outside the slider to exit the Control Center and return to your app.

Resetting App-Specific Text Size

The custom text size remains saved for that specific application even after closing it or restarting your device. If you want to return an app to the system-wide default:

  1. Open the app in question.
  2. Open Control Center and tap the Text Size (AA) icon.
  3. Ensure [Current App] Only is selected.
  4. Move the slider back to the baseline level (the default 100% position indicated by the wider bar marker) or tap All Apps to realign it with your global system font preferences.