How I synced BLE firmware with React Native

Short summary

The author walks through implementing Bluetooth Low Energy communication between a React Native Expo app and custom smartwatch firmware. Key implementation steps: scan and pair using react-native-ble-manager, build packets with checksum validation, establish BLE notifications in a specific sequence (retrieve services → start TX notifications → send RX handshake), implement auto-reconnection on disconnects, and handle platform-specific permissions (iOS vs Android). Includes working code examples and critical timing requirements.

• •React Native + Expo app connects to custom BLE smartwatch firmware via react-native-ble-manager library
• •Proper packet format requires checksums, escaping, and handshake sequence; BLE connection sequence order is critical
• •Auto-reconnection, platform-specific permissions, and timing delays prevent common failure modes

Generated with AI, which can make mistakes.