Success Criterion 1.4.4
Conformance level AA

Mobile App That Ignores the Phone’s System Text-Size Setting

1.4.4 — Resize Text

Scenario

Setting

A fashion e-commerce site's checkout page

What’s wrong

A native mobile app ignores the operating system's text-size / display-zoom setting and offers no in-app way to enlarge text — users who need bigger text have no option at all.

Example

This shows up on a fashion e-commerce site's checkout page: a native mobile app ignores the operating system's text-size / display-zoom setting and offers no in-app way to enlarge text — users who need bigger text have no option at all.

Why it matters

Low-vision people who enlarge text instead of using a screen reader. Here, on a fashion e-commerce site's checkout page, the result is they can't perceive part of the content because of how it's displayed.

How to test

On a native mobile app, change the OS text-size/display-zoom setting (Settings > Display > Font Size) and reopen the app: if text doesn't change size and there's no separate in-app text-size control, it fails.

How to fix

At 200% text size/zoom, all content and controls must remain visible, readable, and usable — nothing clipped, overlapped, or lost.

Outcome

After the fix, the same visitor to a fashion e-commerce site's checkout page can now read the text clearly against its background.

Who is affected

Low-vision people who enlarge text instead of using a screen reader.

Learn more

Understanding Understanding document (opens in a new tab)