✎ Technique: Motion actuation
Ensure that functions that are triggered by moving a device (for example, shaking or tilting) or by gesturing towards the device (so that sensors like a camera can pick up and interpret the gesturing), can also be operated by more conventional user interface components, unless the motion is essential for the function or not using motions or gestures would invalidate the activity.
Users who may be unable to perform particular motions (such as tilting, shaking, or gesturing) because the device may be mounted or users may be physically unable to perform the necessary movement, should still be able to operate all functionality by other means (e.g., touch or voice input).
Some users may accidentally activate sensors due to tremors or other motor impairments. The user must have the ability to turn off motion actuation to prevent accidental triggering of functions.
Examples
✗ Bad example #1
After text is input in a field, shaking a device shows a dialog offering users to undo the input; and, there is no mechanism for disabling motion actuation.
✓ Good example #1
An Undo button next to the text field offers the same functionality.
✗ Bad example #2
A user can tilt a device to advance to the next or a previous page.
✓ Good example #2
Buttons or links are also provided to perform the same function.
✗ Bad example #3
A user can move or pan a device to change the view in an interactive photo.
✓ Good example #3
A text option or button is also available to perform these same functions.
✗ Bad example #4
A user can gesture towards the device to navigate content.
✓ Good example #4
Text option or button is also available to navigate.
