Tilt & Motion Tester
How it works
仕組みThis tester reads your device’s orientation sensors live: alpha (compass rotation), beta (front-to-back tilt), and gamma (left-to-right tilt), each in degrees, plus acceleration from the motion sensor when available. A bubble level renders the readings physically: lay the device flat and the brass bubble settles in the centre ring. It’s a quick way to confirm a phone or tablet’s gyroscope and accelerometer actually work, which no spec sheet can tell you about your particular unit. Sensor data is read in your browser and never leaves the device.
Almost no desktops or laptops carry a gyroscope or accelerometer, so the browser has no sensor to read and the events either never fire or arrive empty. This is a hardware absence, not a bug. Open the page on a phone or tablet and the level springs to life.
Since iOS 13, Safari gates motion and orientation sensors behind an explicit prompt, because sneaky pages once used them for tracking and input snooping. The request must come from a tap, which is what the Start button does. If you declined once, iOS remembers; close the tab and reopen the page, or clear the site’s settings, to be asked again.
Beta is front-to-back tilt (−180° to 180°; 0° lying flat, 90° standing upright) and gamma is left-to-right tilt (−90° to 90°). Alpha is rotation around the vertical axis, 0-360°, but it’s only a true compass heading on devices with a calibrated magnetometer, so expect it to drift or start from an arbitrary zero on many phones.