README

nRF Blinky for Android

nRF Blinky is an application targeting an audience of developers who are new to 
Bluetooth Low Energy. 

The app can be easily modified to work with other devices and may act as a template app.

This very simple application contains two basic features:
 turning on a LED on a connected Bluetooth LE device,
 receiving a Button press and release events from the device.

Based on these 2 states, the derived flows allow to detect:
 button click events (press and release),
 long button click events (pressed for longer than 1 second).

nRF Blinky demonstrates how to implement basic Bluetooth LE operations (blinking)
or binding flows and states (control the LED state based on the button state).

!Scanner !Blinky

In mock flavor an additional UI allows to control the mock environment and the virtual device:

!Mock controls

 Kotlin BLE Library

This app is designed to work as a sample app for the 
Kotlin BLE Library.
It demonstrates how a connection can be handled using a
Service with a clear
separation of the Bluetooth LE logic from the App using a 
Blinky
interface.

The Bluetooth LE logic is implemented in the 
LedButtonServiceImpl
class, which is injected as a "profile". 

 Flavors

The :app module comes in 2 flavors: native and mock. 

The native flavor uses the
native implementation
of Kotlin BLE Library (NativeAndroidEnvironment and CentralManager), while
the mock one uses mock implementation 
(MockAndroidEnvironment and CentralManager with 
mock peripherals 
set up).

 Structure

The nRF Blinky application has been created in Jetpack Compose.

 Dependencies

It is using the following libraries:
 Kotlin BLE Library - handles Bluetooth LE connectivity
 Nordic Common Library for Android - theme and common UI components, e.g. scanner screen
 nRF Logger tree for Timber - logs to nRF Logger app using Timber
 Nordic Gradle Plugins - set of Gradle plugins for building and deployment

The Gradle script is using version catalog for dependency management.

 Modules

The application consists of the following modules:

 :app - the main module, contains the application code
 :scanner - contains the scanner screen navigation entry
 :blinky:spec - contains the Blinky device specification, i.e. Blinky API or the Service UUID
 :blinky:ble - contains the BLE related code, i.e. BlinkyManager implementation
 :blinky:ui - contains the UI related code, i.e. BlinkyScreen
  or BlinkyViewModel implementation,
  and the BlinkyService 

The :blinky:ui and :blinky:spec modules are transport agnostic. 
The Bluetooth LE transport is specified in the :app module using Hilt here. 

The app is using Navigation 3.
The :app module defines navigation in App composable.
The entries are defined in the :scanner 
and :blinky:ui modules.

 Nordic LED and Button Service (LBS)

Service UUID: 00001523-1212-EFDE-1523-785FEABCD123

A simplified proprietary service by Nordic Semiconductor, containing two characteristics:

- LED state (On/Off).
  - UUID: 00001525-1212-EFD

Top issues

Latest release

What's Changed
 Migrate to Kotlin BLE Library 2.0.0-beta09 by @philips77 in https://github.com/nordicsemi/Android-nRF-Blinky/pull/139
 Run BlinkyManager tests in virtual time by @philips77 in https://github.com/nordicsemi/Android-nRF-Blinky/pull/141
 Add Release workflow and unit tests by @philips77 in https://github.com/nordicsemi/Android-nRF-Blinky/pull/140

 Other
 Update dependency no.nordicsemi.gradle:nordic-version-catalog to v2026.10.00 by @renovate[bot] in https://github.com/nordicsemi/Android-nRF-Blinky/pull/132 and https://github.com/nordicsemi/Android-nRF-Blinky/pull/138
 Upd