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# startDeviceMotionUpdates()

Starts device-motion updates without a block handler.

```
func startDeviceMotionUpdates()
```

## Discussion

You can get the latest device-motion data through the [`deviceMotion`](/documentation/CoreMotion/CMMotionManager/deviceMotion) property. You must call [`stopDeviceMotionUpdates()`](/documentation/CoreMotion/CMMotionManager/stopDeviceMotionUpdates()) when you no longer want your app to process device-motion updates. This method uses the reference frame returned by [`attitudeReferenceFrame`](/documentation/CoreMotion/CMMotionManager/attitudeReferenceFrame) for device-motion updates.

---

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