Vehicle Motion Cues on Android: Edge Dots, Permissions, and Safety
Published: · Updated: · Tested on: Samsung SM-S931N, Android 16 / API 36
Android vehicle motion cues show device movement as animated dots around the screen edges while a passenger reads, browses, or watches content in a moving vehicle. The dots avoid the centre of the display and the overlay does not take touch input from the app underneath. Results vary, and the feature must never be used by a driver.
What the edge dots represent
The phone’s motion sensors detect changes in acceleration and orientation. A cue overlay converts those changes into peripheral dot movement. The design provides a visual reference around otherwise stationary screen content.
Sensory conflict is a common explanation in motion-sickness research, but that does not mean a particular visual cue will work the same way for every passenger. Ride conditions, seat position, sleep, smell, visual task, and individual susceptibility can all affect the experience.
Mulmi provides Gentle, Reading, and Strong profiles as starting points for size, spacing, opacity, and response strength. Start low and stop immediately if discomfort increases.
Why Android overlay permission is required
Android’s SYSTEM_ALERT_WINDOW permission allows a TYPE_APPLICATION_OVERLAY window to appear above other apps. Mulmi uses a non-touchable window so reading, browser, video, and messaging controls underneath remain available.
The user must approve this permission from Android settings. Mulmi does not use it to read screen contents, capture audio or video, display full-screen ads, or intercept input.
Ways to start and stop
- The main app button
- A Quick Settings tile
- A home-screen widget
- The ongoing notification
- An optional passenger confirmation notification
These entry points share one overlay state. Optional ride detection never starts cues automatically.
Optional in-vehicle detection without precise GPS
Mulmi subscribes to IN_VEHICLE enter and exit transitions through Android Activity Recognition. It does not request a precise GPS route. When vehicle entry is detected, a notification asks the passenger to tap before starting. Only a session started from that notification can stop automatically after vehicle exit.
If permission is declined or Google Play services is unavailable, the Quick Settings tile and widget continue to work.
Real-device verification
On a Samsung SM-S931N running Android 16, the overlay remained visible above Calculator while touch passed through to the app below. Quick Settings start and stop, live profile changes, rotation, sensor testing, and permission fallback were also checked.
A safer setup order
- Grant overlay permission before the vehicle moves.
- Run the ten-second sensor test.
- Start with Gentle or Reading.
- Use the feature only as a passenger.
- Stop the screen and cues if symptoms increase.
Recurring or severe symptoms should be discussed with a qualified health professional rather than assessed through an app.
Mulmi is not a medical device and does not diagnose, treat, prevent, or cure motion sickness.