ESP32-S3 BLE Flutter Application

A Bluetooth Low Energy (BLE) communication system demonstrating bidirectional data exchange between an ESP32-S3 development board and a Flutter mobile application.

Features

• Device discovery and connection management for ESP32-S3 BLE devices
• Bidirectional data transmission between mobile app and ESP32
• Real-time notification handling and display
• Intuitive user interface with device scanning capabilities
• Graceful connection termination and error handling

Screenshots

Device Scanning	Active Connection

Project Structure

ESP32-S3-BLE-App/
├── flutter_app/              # Flutter mobile application
├── esp32_ble_firmware/       # ESP32 Arduino firmware
└── README.md                 # Project documentation

Getting Started

Prerequisites

• Arduino IDE 1.8.x or later
• Flutter SDK 3.0 or later
• ESP32-S3 development board
• Physical Android or iOS device (BLE not supported in emulators)

ESP32-S3 Firmware Setup

1. Install Arduino IDE

   Download from the official Arduino website.

2. Configure ESP32 Board Support

   • Navigate to File > Preferences
   • Add the following URL to Additional Boards Manager URLs:

     https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json
     

   • Open Tools > Board > Boards Manager
   • Search for "ESP32" and install "ESP32 by Espressif Systems"

3. Install Required Libraries

   • Open Tools > Manage Libraries
   • Search and install "ESP32 BLE Arduino"

4. Upload Firmware

   • Open esp32_ble_firmware.ino from the esp32_ble_firmware/ directory
   • Select your ESP32-S3 board from Tools > Board
   • Connect your ESP32-S3 via USB
   • Click Upload
   • Open Serial Monitor (115200 baud) to verify BLE advertising status

Flutter Application Setup

1. Install Flutter

   Follow the official Flutter installation guide for your operating system.

2. Clone Repository

   https://github.com/senurah/ESP32-S3-Flutter-BLE-Communicator.git

3. Install Dependencies

   flutter pub get

4. Configure Permissions

   Android: Ensure the following permissions are declared in android/app/src/main/AndroidManifest.xml:

   • BLUETOOTH
   • BLUETOOTH_ADMIN
   • BLUETOOTH_SCAN
   • BLUETOOTH_CONNECT
   • ACCESS_FINE_LOCATION

   iOS: Add required keys to ios/Runner/Info.plist:

   • NSBluetoothAlwaysUsageDescription
   • NSBluetoothPeripheralUsageDescription

5. Deploy Application

   flutter run

Usage

Connecting to ESP32-S3

1. Power on your ESP32-S3 device
2. Launch the Flutter application
3. Tap "Scan for Devices"
4. Select "ESP32-S3-BLE-Example" from the discovered devices list

Sending Data

1. Enter your message in the text input field
2. Press Enter or tap Send
3. Verify receipt in the ESP32 Serial Monitor

Receiving Data

The application automatically receives and displays notifications from the ESP32 in real-time through Snackbar messages.

Disconnecting

Press the "Disconnect" button to terminate the BLE connection safely.

Troubleshooting

Issue	Resolution
ESP32 not detected during scan	Verify ESP32 is powered and advertising. Check Serial Monitor output. Restart device if necessary.
Application crashes on launch	Verify all Flutter dependencies are properly installed. Run flutter doctor to check configuration.
Permission errors on Android	Manually grant Bluetooth and Location permissions in device settings.
BLE scan frequency errors	Implement scan throttling with minimum 10-second intervals between scans.

Contributing

Contributions are welcome and encouraged. To contribute:

1. Fork the repository
2. Create a feature branch (git checkout -b feature/improvement)
3. Commit your changes (git commit -am 'Add new feature')
4. Push to the branch (git push origin feature/improvement)
5. Open a Pull Request

Areas for contribution include:

• Bug reports and fixes
• Performance optimizations
• Feature enhancements
• Documentation improvements

License

This project is licensed under the MIT License. See the LICENSE file for details.

Support

For bug reports, feature requests, or general questions:

• Open an issue on GitHub Issues
• Contact the maintainer: GitHub - senurah

Acknowledgments

Built with ESP32 Arduino Core and Flutter's flutter_blue_plus package.