RadioKit is a powerful, object-oriented Arduino library that bridges your hardware and a highly customizable mobile dashboard. It allows you to build industrial-grade control interfaces using simple C++ structures.
- Zero Configuration: The UI is defined in your Arduino code; the app dynamically builds the dashboard upon connection.
- Reliable Communication: Built-in sequence tracking and retransmission for critical commands (VAR_UPDATE, META_UPDATE).
- Spring Physics: High-fidelity spring simulations for sliders, knobs, and joysticks.
- Multiple Transports: BLE (NimBLE), Serial (USB/UART), WiFi (WebSocket), and Cloud relay — all can run simultaneously.
- NVS Persistence: Device configuration (name, passwords, WiFi/Cloud credentials) survives power cycles via ESP32 NVS.
- OTA Firmware Updates: Over-the-air firmware updates via the companion app.
- Filesystem Access: Browse, read, write, and manage files on the device’s LittleFS partition from the app.
- Print Stream: Transport-agnostic
RadioKit.print() API sends messages to the app’s console.
| Widget | Class | Type | Description |
|---|
| Push Button | RK_PushButton | Input | Momentary (true while held) |
| Toggle Button | RK_ToggleButton | Input | Latching on/off |
| Slide Switch | RK_SlideSwitch | Input | iOS-style slide toggle |
| Rocker Switch | RK_RockerSwitch | Input | Rocker-style on/off |
| Slider | RK_Slider | Input | Linear -100..+100 |
| Gas Pedal | RK_GasPedal | Input | Slider variant, springs to min |
| Knob | RK_Knob | Input | Rotary -100..+100 |
| Steering Wheel | RK_Knob (variant) | Input | Knob variant, springs to center |
| Joystick | RK_Joystick | Input | 2-axis (-100..+100 each) |
| Multi Button | RK_MultipleButton | Input | Radio-style button group |
| Multi Select | RK_MultipleSelect | Input | Checkbox-style multi-select |
| LED | RK_LED | Output | RGB indicator |
| Text | RK_Text | Output | Read-only text display |
| Serial Monitor | RK_Serial | Output | Serial console in the app |
| Telemetry | RK_Telemetry | Output | Display-only metrics |
| Transport | Activation | Use case |
|---|
| BLE | RadioKit.startBLE(name) | Local control via RadioKit app (NimBLE on ESP32) |
| Serial | RadioKit.startSerial(Serial) | USB/UART communication (1000000 baud recommended) |
| WiFi | RadioKit.startWiFi() | Local WiFi WebSocket server on port 5555 |
| Cloud | RadioKit.startCloud() | Internet relay via WebSocket (requires WiFi first) |
Multiple transports can run simultaneously. The library broadcasts widget state changes across all active transports automatically.
| Platform | BLE | Serial | WiFi | Notes |
|---|
| ESP32 | [X] NimBLE | [X] USB CDC, FTDI | [X] WebSocket | Fully supported |
| ESP32-S3 | [X] NimBLE | [X] USB CDC | [X] WebSocket | Fully supported |
| ESP32-C3 | [X] NimBLE | [X] USB CDC | [X] WebSocket | WiFi/BLE only |
| nRF52 | [-] | [X] UART | [-] | Serial only |
| STM32 | [-] | [X] UART | [-] | Serial only |
| SAMD | [-] | [X] UART | [-] | Serial only |
BasicSwitch — Minimal BLE example (toggle switch + LED)JoystickMotor — Joystick controlling a servoSliderServo — Slider controlling a servoBLE_RC_Truck — RC truck: dual motor, steeringFilesystem_LED — BLE + LittleFS bulk filesystem demoFsCommandTest — FS command validationWiFiCloudSwitch — BLE + WiFi + Cloud relay: multi-transport demo
