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React Native permissions generator

React Native motion and fitness permission

Reading the pedometer and motion sensors — step counts, activity recognition, device motion — needs android.permission.ACTIVITY_RECOGNITION on Android 10 and later and NSMotionUsageDescription on iOS, which gates the Core Motion activity and pedometer data.

expo-sensors declares both and its Pedometer module requests at runtime. Raw accelerometer and gyroscope readings need no permission on either platform; the grant is for the derived activity data that reveals what the person is doing.

Motion and fitness at a glance

Android grants
android.permission.ACTIVITY_RECOGNITION
iOS Info.plist key
NSMotionUsageDescription
Expo package
expo-sensors
Config plugin
expo-sensors
What it enables
Read the pedometer and motion sensors.
What the user agrees to
Read your step count and movement

The declarations, for Expo and the bare workflow

Expo config

app.json
{
  "expo": {
    "ios": {
      "infoPlist": {
        "NSMotionUsageDescription": "TODO: why this app reads motion data."
      }
    },
    "android": {
      "permissions": [
        "android.permission.ACTIVITY_RECOGNITION"
      ]
    },
    "plugins": [
      "expo-router",
      "expo-sensors"
    ]
  }
}

Prebuild writes these into the native projects; the config plugin is what makes the package's native code part of the build.

Bare workflow, Android

android/app/src/main/AndroidManifest.xml
<uses-permission android:name="android.permission.ACTIVITY_RECOGNITION" />

Bare workflow, iOS

ios/<App>/Info.plist
<key>NSMotionUsageDescription</key>
<string>TODO: why this app reads motion data.</string>

The TODO is deliberate: the usage description is shown in the consent prompt and App Review rejects boilerplate.

Install the library

terminal
npx expo install expo-sensors

Motion and fitness permission, answered

The longer version is in the guide React Native permissions that satisfy both stores.

What permission does React Native need for motion and fitness?
On Android, declare android.permission.ACTIVITY_RECOGNITION in AndroidManifest.xml (or expo.android.permissions in app.json). On iOS, add NSMotionUsageDescription to Info.plist (or expo.ios.infoPlist) with a sentence explaining why — the user reads it in the consent prompt. expo-sensors exposes the runtime request.
Do I still have to request motion and fitness at runtime?
Yes. The declaration only makes the request possible. The first time the feature is used, call the request API from expo-sensors; the operating system shows the prompt ("Read your step count and movement") and remembers the answer. A declared but never requested permission does nothing, and a requested but never declared one fails.
Why was my app rejected over the motion and fitness permission?
Most often the NSMotionUsageDescription string: App Review rejects a missing one at once and a vague or boilerplate one frequently. Write what the app does with the data in your own words. Google Play reviews the declaration against the app's visible features, so a grant no screen uses is also a finding.

Declare every feature the app uses

The React Native permissions generator builds the complete set from the same catalogue — tick each device feature and copy the paired Android grants and iOS usage descriptions, the Expo app.json fragment and the install line together. In the Nodlume workspace the declarations come from the screens themselves: a screen that uses the camera is what adds the camera permission to the Expo Router project it exports.

Open the generator

Other React Native permissions

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