Don’t rely on device motion for functionality
Description
Motion-activated interactions require precise control over movement. This is inaccessible to people with physical and motor disabilities.
This rule gives only a hint and determines DeviceMotionEvent and DeviceOrientationEvent. DeviceMotionEvent
and DeviceOrientationEvent
are part of the Web APIs provided by browsers to allow web applications to access motion data from devices such as smartphones, tablets, and other mobile devices. These events enable developers to create interactive and dynamic web experiences that respond to changes in device orientation or movement.
If both events are detected, then, unless it is an essential part of the application’s purpose, don’t rely on device motion for functionality and use alternative and traditional controls that do the same function.
Purpose
Motion Actuation require that functions operated by motion can also be operated through an interface, and responding to motion can be disabled.
Some users will need to be able to control functions that are controlled by gestures, like pointing or actions, like shaking or tilting, using a more conventional interface. Users who have mobility issues might not be able to interact with these kinds of controls by making the right movements (or making them precisely enough).
Similar to how some users might unintentionally employ these controls, there needs to be a means to turn them off.
How to fix it
- Ensure that gesture and movement-based controls are switchable by users.
- Besides motion and gesture controls, offer a traditional interface (like a button).
- See also:
Provide conventional controls and an application setting for motion activated input
(WCAG Technique G213).
Standard
Accessibility, WCAG 2.1, Success Criterion 2.5.4 Motion Actuation, Level A
Rule ID: motion-actuation