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This is documentation for the next SDK version. For up-to-date documentation, see the latest version (SDK 51).

Expo Pedometer iconExpo Pedometer

GitHub

npm

A library that provides access to the device's pedometer sensor.

Android
iOS

Pedometer from expo-sensors uses the system hardware.Sensor on Android and Core Motion on iOS to get the user's step count, and also allows you to subscribe to pedometer updates.

Installation

Terminal
npx expo install expo-sensors

If you are installing this in an existing React Native app (bare workflow), start by installing expo in your project. Then, follow the additional instructions as mentioned by library's README under "Installation in bare React Native projects" section.

Usage

Pedometer
import { useState, useEffect } from 'react';
import { StyleSheet, Text, View } from 'react-native';
import { Pedometer } from 'expo-sensors';

export default function App() {
  const [isPedometerAvailable, setIsPedometerAvailable] = useState('checking');
  const [pastStepCount, setPastStepCount] = useState(0);
  const [currentStepCount, setCurrentStepCount] = useState(0);

  const subscribe = async () => {
    const isAvailable = await Pedometer.isAvailableAsync();
    setIsPedometerAvailable(String(isAvailable));

    if (isAvailable) {
      const end = new Date();
      const start = new Date();
      start.setDate(end.getDate() - 1);

      const pastStepCountResult = await Pedometer.getStepCountAsync(start, end);
      if (pastStepCountResult) {
        setPastStepCount(pastStepCountResult.steps);
      }

      return Pedometer.watchStepCount(result => {
        setCurrentStepCount(result.steps);
      });
    }
  };

  useEffect(() => {
    const subscription = subscribe();
    return () => subscription && subscription.remove();
  }, []);

  return (
    <View style={styles.container}>
      <Text>Pedometer.isAvailableAsync(): {isPedometerAvailable}</Text>
      <Text>Steps taken in the last 24 hours: {pastStepCount}</Text>
      <Text>Walk! And watch this go up: {currentStepCount}</Text>
    </View>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    marginTop: 15,
    alignItems: 'center',
    justifyContent: 'center',
  },
});

API

import { Pedometer } from 'expo-sensors';

Methods

Android
iOS

Pedometer.getPermissionsAsync()

Checks user's permissions for accessing pedometer.

Returns:

Promise<PermissionResponse>

iOS

Pedometer.getStepCountAsync(start, end)

NameTypeDescription
startDate

A date indicating the start of the range over which to measure steps.

endDate

A date indicating the end of the range over which to measure steps.


Get the step count between two dates.

Returns:

Promise<PedometerResult>

Returns a promise that fulfills with a PedometerResult.

As Apple documentation states:

Only the past seven days worth of data is stored and available for you to retrieve. Specifying a start date that is more than seven days in the past returns only the available data.

Android
iOS

Pedometer.isAvailableAsync()

Returns whether the pedometer is enabled on the device.

Returns:

Promise<boolean>

Returns a promise that fulfills with a boolean, indicating whether the pedometer is available on this device.

Android
iOS

Pedometer.requestPermissionsAsync()

Asks the user to grant permissions for accessing pedometer.

Returns:

Promise<PermissionResponse>

Android
iOS

Pedometer.watchStepCount(callback)

NameTypeDescription
callbackPedometerUpdateCallback

A callback that is invoked when new step count data is available. The callback is provided with a single argument that is PedometerResult.


Subscribe to pedometer updates.

Returns:

EventSubscription

Returns a Subscription that enables you to call remove() when you would like to unsubscribe the listener.

Pedometer updates will not be delivered while the app is in the background. As an alternative, on Android, use another solution based on Health Connect API. On iOS, the getStepCountAsync method can be used to get the step count between two dates.

Interfaces

Android
iOS

PermissionResponse

An object obtained by permissions get and request functions.

PermissionResponse Properties

NameTypeDescription
canAskAgainboolean

Indicates if user can be asked again for specific permission. If not, one should be directed to the Settings app in order to enable/disable the permission.

expiresPermissionExpiration

Determines time when the permission expires.

grantedboolean

A convenience boolean that indicates if the permission is granted.

statusPermissionStatus

Determines the status of the permission.


Types

Android
iOS

PedometerResult

NameTypeDescription
stepsnumber

Number of steps taken between the given dates.

Android
iOS

PedometerUpdateCallback()

Callback function providing event result as an argument.

NameType
resultPedometerResult
Android
iOS

PermissionExpiration

Literal Type: multiple types

Permission expiration time. Currently, all permissions are granted permanently.

Acceptable values are: 'never' | number

Android
iOS

Subscription

A subscription object that allows to conveniently remove an event listener from the emitter.

NameTypeDescription
remove() => void

Removes an event listener for which the subscription has been created. After calling this function, the listener will no longer receive any events from the emitter.

Enums

Android
iOS

PermissionStatus

PermissionStatus Values

DENIED

PermissionStatus.DENIED = "denied"

User has denied the permission.

GRANTED

PermissionStatus.GRANTED = "granted"

User has granted the permission.

UNDETERMINED

PermissionStatus.UNDETERMINED = "undetermined"

User hasn't granted or denied the permission yet.