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# startAccelerometerUpdates(to:withHandler:)

Starts accelerometer updates on an operation queue and with a specified handler.

```
func startAccelerometerUpdates(to queue: OperationQueue, withHandler handler: @escaping CMAccelerometerHandler)
```

## Parameters

`queue`

An operation queue provided by the caller. Because the processed events might arrive at a high rate, using the main operation queue is not recommended.

`handler`

A block that is invoked with each update to handle new accelerometer data. The block must conform to the [`CMAccelerometerHandler`](/documentation/CoreMotion/CMAccelerometerHandler) type.

## Discussion

You must call [`stopAccelerometerUpdates()`](/documentation/CoreMotion/CMMotionManager/stopAccelerometerUpdates()) when you no longer want your app to process accelerometer updates.

---

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