---
title: xTrueNorthZVertical
framework: coremotion
role: symbol
role_heading: Type Property
path: coremotion/cmattitudereferenceframe/xtruenorthzvertical
---

# xTrueNorthZVertical

A reference frame where the Z axis is vertical and the X axis points to the geographic north pole.

## Declaration

```swift
static var xTrueNorthZVertical: CMAttitudeReferenceFrame { get }
```

## Mentioned in

Getting processed device-motion data

## Discussion

Discussion Use this option to determine the attitude of the device relative to true north. For example, you might use this to implement more precise navigation. The yaw (Z-axis) value in CMAttitude is 0 when the X axis is aligned with true north. The device must have a magnetometer and that sensor must be available. Location services must also be available to calculate the difference between magnetic and true north. If the magnetometer isn’t currently calibrated, Core Motion prompts the person to move the device to calibrate it.

## See Also

### Getting the reference frames

- [xArbitraryZVertical](coremotion/cmattitudereferenceframe/xarbitraryzvertical.md)
- [xArbitraryCorrectedZVertical](coremotion/cmattitudereferenceframe/xarbitrarycorrectedzvertical.md)
- [xMagneticNorthZVertical](coremotion/cmattitudereferenceframe/xmagneticnorthzvertical.md)