Tilt-Based Scrolling With No Conventional Control Option

2.5.4 — Motion Actuation

Scenario

A fitness app's workout tracker

Tilt-based scrolling/parallax input without a conventional control.

window.addEventListener('deviceorientation', (e) => {
  workoutList.scrollTop += e.beta * 2; // tilt is the only way to scroll the list
});

A person exercising with the phone mounted on a treadmill can't tilt it to scroll and gets stuck on the first exercise.

Try to scroll/trigger parallax via a conventional control instead of tilting: if tilt is the only input method, it fails.

Remove the tilt handler, or make it opt-in, and rely on ordinary scrolling as the default.

.workout-list { overflow-y: auto; touch-action: pan-y; }

A user scrolls the workout list with a normal swipe or trackpad, with no tilting required.

Wheelchair users with a mounted device, people with limited wrist rotation, and anyone using the app hands-free on a stand.