A privacy-friendly Android step tracker that runs entirely on the phone — no watch, no account, no cloud (optional self-hosted Home Assistant sync).
- Steps are counted from the phone's own hardware: the built-in
TYPE_STEP_COUNTER, with an accelerometer peak-detector fallback on devices that lack one. It never reads steps from a watch. - Targets & achievements are computed from age, sex, height, weight and activity level: daily step goal, stride length, distance, calories, BMI, max heart rate (208 − 0.7 × age) and heart rate zones.
- Life expectancy is estimated from your age, sex, BMI and your average daily steps, shown as a live countdown ticking down every second.
- Home Assistant sync (optional) pushes each day's progress to your own Home Assistant instance once per day over your home Wi-Fi.
 |
 |
| Area | Details |
|---|---|
| Dashboard | Today's steps, goal progress, distance, calories, active minutes, BMI, HR zones, current streak |
| Life expectancy | Estimated lifespan from age, sex, BMI and average steps over the last 30 days, displayed as a live second-by-second countdown |
| Achievements | 11 badges: first steps, 1k / 5k / 10k / 20k steps, 5 km / 10 km, 500 kcal, healthy BMI, 3-day and 7-day streaks |
| Profile | Age, sex, height, weight, activity level, optional custom step goal; live targets preview |
| History | Last 60 days in a scrollable list plus a 14-day bar chart, with per-day steps, distance and calories |
| Wellness | Sedentary reminders (optional notifications to stand up and move), walking advice, a 5-minute morning routine and gentle no-equipment exercises for skeleton and muscle |
| Backup | Export the whole SQLite database to a file (SAF) and restore it later or on another device |
| Background | Foreground service keeps the step counter alive in the background and flushes data to SQLite every 30 s (battery-friendly) |
| Home Assistant | Single sensor sensor.healthx_steps (state = latest day, history attribute = every day); retries while away and catches up missed days |
- All data stays on-device in a local SQLite database (
health_monitor.db). - No network calls, no analytics, no ads, no account.
- You can export/restore the database yourself via the Profile tab.
- In Home Assistant, click your username → Security → Long-lived access tokens → Create token and copy it.
- In the app: Profile → Home Assistant sync, enter your server URL (e.g.
http://192.168.8.17:8123) and the token, then enable the switch. - The app maintains ONE entity:
sensor.healthx_steps. Its state is the latest day's step count; attributes includedate,distance_km,caloriesand ahistorymap ({"2026-08-24": 7796, ...}) with the last 30 days. Opening the app also refreshes the sensor.
How it works: a daily WorkManager job runs on connected Wi-Fi and updates the sensor with all data that has not been sent yet (older versions created one entity per day; those are deleted automatically). If Wi-Fi is unavailable — for example you are away — the app retries every 30 minutes and catches up later, so skipped days are not lost: when you are back home each missing day appears in the history attribute under its own date.
Past days / statistics: besides the state update, every sync also imports all days into Home Assistant's long-term statistics via recorder.import_statistics (statistic_id: sensor.healthx_steps, source healthx). That means past days show up immediately: check Developer tools → Statistics, add a Statistics Graph card (period: day), or open the entity's more-info dialog.
- Activity recognition — required on Android 10+ to read the built-in step counter.
- Notifications — Android 13+ notification permission for the background tracking service and sedentary reminders.
- Internet / network state — only used for the optional Home Assistant sync on your local network.
- Kotlin, Android Gradle Plugin 8.2.2, Gradle 8.2
minSdk 26(Android 8.0),targetSdk 34(Android 14)- ViewBinding, Material 3, WorkManager
Build a debug APK:
./gradlew assembleDebug
# output: app/build/outputs/apk/debug/app-debug.apkThis repository also contains a GitHub Actions workflow (.github/workflows/build-debug.yml) that builds the debug APK on every push and uploads it as the health-monitor-debug-apk artifact.
app/src/main/java/com/example/healthmonitor/
├── MainActivity.kt # Entry point; wires stores/tracker, starts the service
├── HealthApp.kt # Application; DB-backed singletons + legacy prefs migration
├── data/ # SQLite layer, stores, calculations, achievements
│ ├── HealthDatabase.kt # SQLiteOpenHelper: daily_stats, achievements, profile
│ ├── StatsStore.kt # Steps / history / backup
│ ├── ProfileStore.kt # User profile
│ ├── TargetsCalculator.kt # Goals, stride, distance, calories, BMI, HR zones
│ ├── LifeExpectancyCalculator.kt # Estimated lifespan + habit adjustments
│ ├── Achievements.kt # Badge definitions + check/earn logic
│ └── DailyStat.kt, UserProfile.kt
├── sensor/
│ ├── StepTracker.kt # Step counter + accelerometer fallback
│ └── StepService.kt # Foreground service, 30 s flush tick
├── advice/
│ ├── SedentaryReminder.kt # Alarm scheduling for sit-less reminders
│ └── SedentaryReminderReceiver.kt # Moves-you reminder notification
├── sync/
│ ├── SyncManager.kt # Catch-up logic: sends every unsynced day over Wi-Fi
│ ├── SyncScheduler.kt # WorkManager: daily periodic sync + 30 min retry
│ ├── SyncWorker.kt # Worker that performs one sync
│ ├── BootReceiver.kt # Re-arms WorkManager + sedentary alarms after reboot
│ └── HomeAssistantClient.kt # REST POST /api/states/<entity>
└── ui/
├── DashboardFragment.kt
├── HistoryFragment.kt
├── AdviceFragment.kt
├── AchievementsFragment.kt
├── ProfileFragment.kt
└── view/ # StepsBarChartView
Heart rate zones shown on the dashboard are estimates computed from age for wellness tracking only, and the life-expectancy countdown is a statistical estimate based on your recent habits — improving your steps and BMI genuinely improves it. This app is not a medical device and must not be used to diagnose, treat or monitor medical conditions.
For an overview of all my other projects, see https://adegard.github.io/blog/