Here’s a fun exercise involving testing for accessibility on a mobile app. Increase your device’s text size setting and see if it works on an app. In addition to the text size itself, the interface must also remain readable and usable.
If conducting an accessibility assessment, supporting the device’s text size setting should be required—unless the app provides its own method to do so. If you’re referencing WCAG 2.0, this falls under 1.4.4 Resize text (level AA).
In both Android and iOS device settings, increase text size with the slider control. Optionally turn on the toggle/switch for larger sizes.
In Android, navigate to Settings / Accessibility / Vision / Font Size
In iOS, navigate to Settings / General / Accessibility / Larger Text
After doing so, open an app and notice (or not notice) the difference. It should work in the platform’s default apps such as weather. Some popular native apps such as Twitter support this pretty well.
iOS weather app with default text:
iOS weather app with large text: