Android app · Developer

BLE Finder

Bluetooth Low Energy scanner for finding nearby devices and inspecting signals.

Get it on Google Play ↗ Source on GitHub ↗

BLE Finder is an Android app for finding nearby Bluetooth Low Energy devices by turning raw RSSI signal changes into a radar-style tracking experience. It is built for people trying to locate wearables, earbuds, styluses, trackers, and other BLE peripherals using visual hot/cold feedback and optional audio pings. No hosted demo is configured because the primary artifact is a mobile app.

Project Overview

The app scans nearby BLE advertisements, filters and sorts discovered devices, and lets the user focus on one target at a time. It estimates proximity from RSSI, smooths noisy signal changes, keeps local scan logs in Room, and includes Play Store-ready assets plus a separate privacy policy site for publication support.

Key Features

• 📡 Low-latency BLE scanning with Android permission handling for modern Bluetooth APIs.
• 🎯 Radar tracking screen with RSSI-based hot, warm, and cold proximity states.
• 🔊 Optional audio ping feedback that changes frequency and interval as signal strength improves.
• 🧭 Device filtering and sorting by type, signal strength, advertised name, and last-seen time.
• 🗃️ Local Room database for tracked devices and scan-history logs.
• 🧹 Log retention controls with purge support for old scan entries.
• 🧪 JVM, Robolectric, Compose UI, and Roborazzi screenshot tests.
• 🛒 Generated Google Play graphics, phone screenshots, tablet screenshots, and listing copy.

Architecture Overview

The project follows a lightweight clean-architecture layout. Compose screens render state and delegate actions to ViewModels, ViewModels call domain use cases, and use cases depend on repository interfaces. Data implementations wrap Android Bluetooth scanning, Room DAOs, and AudioTrack-based audio feedback.

Scan flow: the user grants Bluetooth/location permissions, BleScanner starts a low-latency BLE scan, scan results are converted into BleDevice models, the UI filters/sorts them, and tracking screens calculate smoothed RSSI and estimated distance for a selected MAC address.

Design patterns used here include repository interfaces, use-case classes, manual dependency injection through AppContainer, Kotlin Flow for asynchronous scan streams, and immutable UI state collected by Compose.

Tech Stack & Libraries

Configuration

Runtime settings are exposed in the app's Settings screen:

Usage / Quick Start

Run From Android Studio

1. Open the BLEFinder folder in Android Studio.
2. Select a physical Android device with Bluetooth enabled.
3. Run the app configuration.
4. Grant Bluetooth and location permissions when prompted.
5. Tap Scan Devices, then choose a discovered peripheral to open the radar tracker.

Run From The Terminal

cd BLEFinder
./gradlew assembleDebug
adb install -r app/build/outputs/apk/debug/app-debug.apk
adb shell monkey -p com.michael.blefinder 1

Generate Play Store Assets

cd BLEFinder
./gradlew generatePlayStoreAssets

tablet screenshots, and listing copy.

API Reference

Not applicable. BLE Finder is a local Android application and does not expose an HTTP API, CLI API, SDK, or server endpoint. Retrofit, OkHttp, and Moshi are present as dependencies, but no repository evidence shows a configured network API client.

Testing

Run all JVM unit, Robolectric, and non-screenshot Compose tests:

./gradlew testDebugUnitTest

Run Android instrumented tests on a connected device or emulator:

./gradlew connectedDebugAndroidTest

Regenerate Roborazzi screenshots and Play Store graphics:

./gradlew generatePlayStoreAssets

Test files live under app/src/test/java/com/michael/blefinder/ and app/src/androidTest/java/com/michael/blefinder/. Existing names use *Test.kt, while Play Store screenshot tests are grouped under app/src/test/java/com/michael/blefinder/playstore/.

Coverage reporting is not configured in the repository.

Deployment

Debug Deployment

Use Android Studio or install the Gradle-generated APK directly:

./gradlew assembleDebug
adb install -r app/build/outputs/apk/debug/app-debug.apk

Release Build

Set signing credentials, then build the release APK or Android App Bundle:

export KEYSTORE_PATH="$PWD/my-upload-key.jks"
read -rsp "Store password: " STORE_PASSWORD && export STORE_PASSWORD
read -rsp "Key password: " KEY_PASSWORD && export KEY_PASSWORD

./gradlew assembleRelease
./gradlew bundleRelease

Release artifacts are generated under app/build/outputs/. Docker, docker-compose, and backend health checks are not applicable because this repository builds a native Android app with no server component.

Privacy Policy Site

The privacy policy lives in the sibling ../BLEFinder-pv/ project and is configured for Netlify static hosting.

cd ../BLEFinder-pv
python3 -m http.server 8080 --directory .