Bluetooth Low Energy (BLE) on Android

A Deep Dive into the Technology and Its Applications

Introduction to BLE

Bluetooth Low Energy (BLE) is a wireless technology for short-range communication with low power consumption. It's designed for applications that require frequent but low-power connections, like fitness trackers and IoT devices.

Difference between BLE andClassic Bluetooth

Feature Bluetooth Low Energy (BLE) Classic Bluetooth
Power Consumption Very low – optimized for long battery life Higher – drains battery faster
Data Rate ~125 Kbps to 2 Mbps Up to 3 Mbps
Use Case Short-burst data (IoT, sensors) Continuous streaming (audio, files)
Connection Time Fast (few milliseconds) Slower (up to a second)
Compatibility Android 4.3+ and iOS 5+ Available since earlier versions
Applications Smartwatches, fitness bands, smart home Headphones, car stereos, file transfer
Range Up to 100 meters Typically 10–100 meters
Profiles Used GATT (Generic Attribute Profile) Standard profiles (A2DP, HSP, etc.)

How Does BLE Work

How BLE Works

Key BLE Features in Android

  • BLE Scanning: Discover nearby BLE devices using BluetoothLeScanner.
  • GATT Client: Connect to BLE peripherals and interact with services/characteristics using the GATT protocol.
  • GATT Server (Peripheral Mode): Available from Android 5.0+, allowing the device to act as a BLE peripheral.
  • BLE Advertising: Broadcast custom BLE data like beacons using the BluetoothLeAdvertiser.
  • Background Scanning: Scan for BLE devices even when the app is not in the foreground (battery-optimized).
  • Security and Pairing: Supports bonding, secure connections, and encrypted communication.
  • Permissions: Requires permissions such as BLUETOOTH_SCAN, BLUETOOTH_CONNECT, and location access.
  • Low Power Consumption: Designed for minimal battery drain during BLE communication.

    • Implementing Background Services in BLE

    1. Allows the BLE app to keep scanning and listening for notifications even when not in the foreground.
    2. Essential for apps that need continuous monitoring, like health trackers.

    Conclusion

    Bluetooth Low Energy is a powerful technology for modern applications, especially in the IoT space. With its low power consumption and efficient data transfer, it has become the go-to choice for many developers.

    Understanding its features and how to implement them in Android is crucial for building efficient and responsive applications.