This is a proof of concept of adding wake word functionality to home assistnt companion app. This functionality has since been included in the companion. You can still use this if you prefer it over changing settings in the companion when you want to activate a wake word, but it will not be developed further by me. As always, feel free to fork it if you want.
⚠️ TESTING PRE-RELEASE⚠️ This app is currently in testing/pre-release state. Features may be incomplete or unstable. Please report any issues you encounter.
Transform any old Android phone or tablet into an always-listening wake word device for Home Assistant Assist — with zero typing required.
⬇️ Download Proof of Concept APK (v1.0.0-poc)
🧪 Proof of Concept Release for Public Testing
This build is confirmed working on Android 13 and Android 14 devices. This release is preserved for public testing and demonstration purposes.
⚠️ Known Issue: Crashes on Android 10 devices. An Android 10 compatibility fix is in development.💡 You may need to enable "Install from unknown sources" in your Android settings to install the APK.
All Releases | Latest Development Builds
This app provides a simple 3-step wizard that configures your Android device to:
- Listen for the wake word "Hey Mycroft" (always-on, using built-in wake word detection)
- Trigger Home Assistant Assist when the wake word is detected
- Stay running reliably in the background with no user intervention
No external apps required, no typing, no configuration files — just tap through the wizard and you're done!
- Download
- Features
- Requirements
- Quick Start
- Detailed Setup Guide
- How It Works
- Building From Source
- Troubleshooting
- For Developers
- Contributing
- License
| Feature | Description |
|---|---|
| 🎙️ Always-On Listening | Wake word detection runs continuously in the background |
| 🏠 Home Assistant Integration | Opens HA Assist directly when triggered |
| 📱 One-Tap Setup | 3-step wizard guides you through setup |
| 🔋 Battery Optimized | Efficient on-device neural network processing |
| 🔒 On-Device Processing | All wake word detection happens locally — no cloud required |
| ⚡ No External Apps | Everything runs within this single app |
- Android phone or tablet (great for repurposing old devices!)
- Built-in or external microphone
- Android 7.0 (Nougat) or later — API level 24+
- Home Assistant Companion App — installed and signed in
- Internet connection to Home Assistant (local network is fine)
- Download the APK and install it on your Android device
- Open the app and follow the 3-step wizard
- Say "Hey Mycroft" — Home Assistant Assist will open!
That's it! The wizard handles all the configuration automatically.
Tap "Grant Microphone Permission" to allow the app to listen for wake words.
Why it's needed: The app needs microphone access to detect when you say "Hey Mycroft". All audio processing happens locally on your device — no audio is sent to any server.
Tap "Disable Battery Optimization" to ensure the wake word detection runs reliably.
Why it's needed: Android may stop background services to save battery. Disabling optimization for this app ensures it keeps running.
Tap "Start Wake Word Detection" to begin listening.
What happens:
- A foreground service starts with a persistent notification
- The app continuously listens for "Hey Mycroft"
- When detected, Home Assistant Assist opens automatically
┌─────────────────────────────────────────────────────────────────┐
│ Your Android Device │
├─────────────────────────────────────────────────────────────────┤
│ │
│ ┌─────────────────────────────────────────────────────────┐ │
│ │ Easy HA Wakeword App │ │
│ │ │ │
│ │ ┌─────────────────┐ │ │
│ │ │ Microphone │ ──── Captures audio │ │
│ │ └────────┬────────┘ │ │
│ │ │ │ │
│ │ ▼ │ │
│ │ ┌─────────────────┐ │ │
│ │ │ OpenWakeWord │ ──── Neural network detection │ │
│ │ │ (ONNX Runtime) │ "Hey Mycroft" → 0.85 score │ │
│ │ └────────┬────────┘ │ │
│ │ │ │ │
│ │ │ Score > threshold? │ │
│ │ ▼ │ │
│ │ ┌─────────────────┐ │ │
│ │ │ Launch Intent │ ──── Opens Home Assistant Assist │ │
│ │ └─────────────────┘ │ │
│ └─────────────────────────────────────────────────────────┘ │
│ │
│ ┌─────────────────┐ │
│ │ Home Assistant │ ──── Voice assistant ready │
│ │ Companion │ │
│ └─────────────────┘ │
│ │
└─────────────────────────────────────────────────────────────────┘
The app uses OpenWakeWord for on-device wake word detection:
- ONNX Runtime for efficient neural network inference
- Mel-spectrogram processing for audio feature extraction
- Embedding model for audio representation
- Wake word classifier for "Hey Mycroft" detection
All processing happens locally — no internet required for detection!
| Requirement | Version |
|---|---|
| Android Studio | Arctic Fox (2020.3.1) or later |
| JDK | 17 |
| Android SDK | 34 (compileSdk) |
| Kotlin | 1.9.10 |
# Clone the repository
git clone https://github.com/R00S/easy-android-ha-wakeword-app.git
cd easy-android-ha-wakeword-app
# Build debug APK
./gradlew assembleDebug
# Build release APK
./gradlew assembleRelease
# Install directly to connected device
./gradlew installDebugAPK files are generated in:
app/build/outputs/apk/debug/app-debug.apk
app/build/outputs/apk/release/app-release-unsigned.apk
easy-android-ha-wakeword-app/
├── app/
│ ├── src/main/
│ │ ├── java/com/roos/easywakeword/
│ │ │ ├── SetupWizardActivity.kt # Main wizard UI
│ │ │ └── wakeword/
│ │ │ ├── WakeWordEngine.kt # ONNX model runner
│ │ │ └── WakeWordService.kt # Background service
│ │ ├── assets/
│ │ │ ├── embedding_model.onnx # Audio embedding model
│ │ │ ├── melspectrogram.onnx # Mel-spectrogram model
│ │ │ └── hey_mycroft.onnx # Wake word model
│ │ ├── res/
│ │ │ ├── layout/ # XML layouts
│ │ │ ├── values/ # Strings, colors, themes
│ │ │ └── drawable/ # Icons and graphics
│ │ └── AndroidManifest.xml
│ └── build.gradle
├── build.gradle
├── settings.gradle
├── THIRD_PARTY_NOTICES.md # Third-party licenses
└── README.md
| Issue | Solution |
|---|---|
| Service not running | Check for persistent notification; restart via wizard |
| Microphone permission denied | Grant mic permission in app settings |
| Battery optimization killing service | Disable battery optimization for this app |
| Threshold too high | Wake word requires clear pronunciation |
| Issue | Solution |
|---|---|
| HA Companion not installed | Install from Play Store |
| Not signed in to HA | Open HA app and complete sign-in |
| Wrong app version | Ensure you have the latest HA Companion |
- Disable battery optimization for this app
- Check for "App hibernation" in Android settings (Android 12+)
- Lock app in recent apps (swipe down to lock)
| Device/Manufacturer | Common Issue | Solution |
|---|---|---|
| Samsung | Aggressive battery optimization | Disable in Device Care |
| Xiaomi/MIUI | Autostart blocked | Enable autostart in Security app |
| Huawei/EMUI | App killed in background | Add to "Protected apps" |
| OnePlus | Battery optimization | Disable in Battery settings |
| Permission | Purpose | Required |
|---|---|---|
RECORD_AUDIO |
Wake word detection | Yes |
FOREGROUND_SERVICE |
Background listening | Yes |
FOREGROUND_SERVICE_MICROPHONE |
Microphone in foreground service | Yes |
POST_NOTIFICATIONS |
Show status notifications | Android 13+ only |
REQUEST_IGNORE_BATTERY_OPTIMIZATIONS |
Prompt for battery exemption | Optional |
The app bundles the "Hey Mycroft" wake word model from OpenWakeWord.
Model details:
- Wake word: "Hey Mycroft"
- Detection threshold: 0.05
- Processing: Real-time (80ms chunks)
- Framework: ONNX Runtime
Contributions are welcome! Please feel free to submit issues and pull requests.
- Fork the repository
- Create your feature branch (
git checkout -b feature/amazing-feature) - Commit your changes (
git commit -m 'Add amazing feature') - Push to the branch (
git push origin feature/amazing-feature) - Open a Pull Request
If you find this project useful, consider buying me a coffee!
This project is licensed under the MIT License — see the LICENSE file for details.
This project uses code from the following open-source projects (Apache 2.0 licensed):
- OpenWakeWord by David Scripka
- OpenWakeWord for Android by Hasanat Ahmed Lodhi
See THIRD_PARTY_NOTICES.md for full license details.
- Home Assistant — The amazing home automation platform
- OpenWakeWord — Open source wake word detection
- OpenWakeWord for Android — Android port inspiration
- ONNX Runtime — Efficient neural network inference
Made with ❤️ for the Home Assistant community