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  "documentType" : "symbol",
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# unknown

A Boolean indicating whether the type of motion is unknown.

```
var unknown: Bool { get }
```

## Discussion

This property is set to <doc://com.apple.documentation/documentation/Swift/true> when there is no way to estimate the current type of motion. For example, this property might be <doc://com.apple.documentation/documentation/Swift/true> if the device was turned on recently and not enough motion data had been gathered to determine the type of motion.

---

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