---
title: NSMotionUsageDescription
framework: Bundle Resources
role: symbol
role_heading: Property List Key
platforms: [iOS 7.0+, iPadOS 7.0+, Mac Catalyst 7.0+, macOS 10.15+, visionOS 1.0+]
path: bundleresources/information_property_list/nsmotionusagedescription
---

# NSMotionUsageDescription

A message that tells people why the app is requesting access to the device’s motion data.

## Discussion

> **important:** This key is required if your app uses APIs that access the device’s motion data, including [CMSensorRecorder](../../coremotion/cmsensorrecorder.md), [CMPedometer](../../coremotion/cmpedometer.md), [CMMotionActivityManager](../../coremotion/cmmotionactivitymanager.md), and [CMMovementDisorderManager](../../coremotion/cmmovementdisordermanager.md). If you don’t include this key, your app will crash when it attempts to access motion data.

## See Also

### Motion

- [NSFallDetectionUsageDescription](../information-property-list/nsfalldetectionusagedescription.md)