Summary:
Functions operated by device motion can be disabled and have an alternative input method.
Details:
When device motion or user motion (e.g., shaking, tilting, or gestures picked up by the device’s camera) are used for interaction, an alternative input method should be provided to perform an equivalent action unless the motion is essential for the function and doing so would invalidate the activity. When alternatives are not provided, users with motor impairments or users who are unable to perform gestures or actuate sensors on the device will not be able to access the functionality on the page.
Note: This guideline concerns input through sensors which respond directly to motions such as tilting, shaking, or gesturing towards a device. It is not intended to cover the motion of users through space as registered by geolocation sensors or beacons, or events observed by the device other than intentional gestures by the user. It also does not cover indirect motion associated with operating a keyboard, pointer, or assistive technology.
Examples of equivalent user interface controls:
- After text input in a field, shaking a device shows a dialog offering users to undo the input. A cancel button next to the text field offers the same functionality - activating it reverts to the content (if any) that was shown before the user input replaced it.
- A user can tilt a device to advance to the next or a previous page. Buttons or links are also provided to perform the same function.
- A user can move or pan a device to change the view in an interactive photo. A control is also available to perform the same function.
- A user can gesture towards the device to navigate content. Controls are also available to navigate.
