Motion Actuation - Success Criterion 2.5.4 (Level A)

Question

If your application uses motion to operate a component, is there alternative functionality (e.g. button, link) to provide the same result?

Why is this important?

Mobile devices can use motion sensor technology to operate certain features. For example, tilting the device right to advance forward and left to move backward through a sequence of steps. This functionality can be troublesome for users who have mobility impairments, tremors, or who mount their device to their wheelchair. To ensure access to all users, all motion sensor features should also be operable using a standard interface as well as the option to disable the motion completely.

Whom does it benefit?

Example 1

As a person with cerebral palsy who mounts a tablet to my wheelchair,
I want alternative functionality such as buttons to control motion sensored applications
so that I can operate them without unmounting the tablet from my wheelchair.

Example 2

As a person with tremors,
I want to disable motion-based controls and use traditional interface controls
so that I can use my device without fear of activating something unintentionally.

What should you do?

Ensure all motion functionality can be operated using an alternative method and the user has the ability to disable motion controls.

How do you do it?

Provide alternative functionality such as keyboard interface controls.
Provide a way for the user to turn off motion functionality to prevent accidental actuation.

Exception: When the motion is supported through an accessibility interface or it is essential for the function and doing so would invalidate the activity.