React Native BLE Manager is a Bluetooth Low Energy (BLE) library for React Native applications. It provides a comprehensive set of functions to interact with BLE devices, including scanning, connecting, and reading/writing characteristics.

Pros

• Cross-platform support for both iOS and Android
• Extensive API covering most BLE operations
• Active community and regular updates
• Well-documented with examples and TypeScript support

Cons

• Requires native module linking, which can be complex for some developers
• Performance may vary depending on device and OS version
• Limited support for background operations on iOS
• Some users report occasional stability issues with certain devices

Code Examples

Scanning for BLE devices:

import BleManager from 'react-native-ble-manager';

BleManager.start({ showAlert: false });

BleManager.scan([], 5, true).then(() => {
  console.log('Scan started');
});

BleManager.addListener('BleManagerDiscoverPeripheral', (device) => {
  console.log('Discovered device:', device);
});

Connecting to a device and reading a characteristic:

BleManager.connect(deviceId)
  .then(() => {
    console.log('Connected');
    return BleManager.retrieveServices(deviceId);
  })
  .then((peripheralInfo) => {
    console.log('Peripheral info:', peripheralInfo);
    return BleManager.read(deviceId, serviceUUID, characteristicUUID);
  })
  .then((readData) => {
    console.log('Read:', readData);
  })
  .catch((error) => {
    console.log('Error:', error);
  });

Writing to a characteristic:

const data = [0x01, 0x02, 0x03];
BleManager.write(deviceId, serviceUUID, characteristicUUID, data)
  .then(() => {
    console.log('Write successful');
  })
  .catch((error) => {
    console.log('Write error:', error);
  });

Getting Started

1. Install the library:

   npm install react-native-ble-manager
   

2. Link the native modules:

   npx react-native link react-native-ble-manager
   

3. Import and initialize in your React Native app:

   import BleManager from 'react-native-ble-manager';
   
   // In your app's entry point or main component
   componentDidMount() {
     BleManager.start({ showAlert: false })
       .then(() => {
         console.log('BLE Manager initialized');
       })
       .catch((error) => {
         console.log('BLE Manager initialization error:', error);
       });
   }
   

4. Add necessary permissions to your app's Info.plist (iOS) and AndroidManifest.xml (Android) files.