Development of Wear OS Integration for AiCarer

Android Developer for Wear OS Integration

Project Brief
We're seeking a skilled Android developer to build a Wear OS integration for AiCarer, our health monitoring platform. This project involves creating a library module that enables our app to collect health metrics from Wear OS devices in both continuous and on-demand modes.

About AiCarer
AiCarer is a digital health platform that enables real-time, proactive monitoring of elderly or vulnerable individuals. We monitor health metrics from wearable devices to detect early warning signs and risk events (e.g., falls, stress, wandering). We're now expanding to support Wear OS devices.



Project Scope

Required Deliverables

A complete Android library module (AAR) that implements:

- Background service for collecting continuous heart rate and steps data
- On-demand accelerometer and location collection for incident recording
- Battery level monitoring and reporting
- Data transmission to the phone app via Wear Data Layer API
- Formatting data for our backend API
- Error handling for sensor unavailability and network issues


Final deliverables should include:

- Compiled wear-integration-release.aar file
- Source code for the integration module
- Documentation of implementation details and battery optimization choices
- Brief documentation of testing performed, including device models tested



Health Metrics Implementation Requirements

Continuous Monitoring (Always Running)

- Heart Rate: Sample via Sensor.TYPE_HEART_RATE
- Steps: Track via Sensor.TYPE_STEP_COUNTER
- Battery Level: Report current battery percentage of the wearable device

On-Demand Incident Recording

- Accelerometer: When triggered, collect samples at ~1-second intervals for 30 seconds
- Location: Capture start location when incident recording begins and end location when it stops
- Package all collected data into a standardized IncidentData object
- Support both automatic (time-based) and manual stopping of incident recording
- Incident recording will be triggered by the phone app, with the Wear OS service responding to requests rather than initiating recordings autonomously

Technical Requirements

Wear OS Service

- Implement as a foreground service with notification
- Register appropriate sensor listeners
- Optimize battery usage via adaptive sampling rates
- Handle watch sleep/wake cycles properly
- Request and handle required permissions
- The service should remain active during typical daily use, restarting automatically if terminated by the system, while balancing reliability with battery efficiency


Data Layer Communication

- Use MessageClient/DataClient to transmit metrics to phone
- Handle connection interruptions and retries
- Support both phone-connected and standalone modes where possible


Interface Implementation

- Implement our WearIntegration interface exactly as defined in the demo project
- Ensure all methods work as documented in the comments


Error Handling

- Graceful degradation when sensors are unavailable
- Local caching for offline operation
- Clear logging for troubleshooting


Device Compatibility

- The solution should work on Wear OS 2.0+ devices
- Focus on current Wear OS 3.0+ watches (Google Pixel Watch, Samsung Galaxy Watch 4/5/6, etc.)



Data Format

We expect health data to match this structure (user-specific fields and database IDs will be added by our main app and backend):

json{
"deviceId": "2345678901",
"deviceName": "Pixel Watch",
"heartRate": 78,
"steps": 2300,
"accelData": "",
"batteryLevel": 65,
"timestamp": "2025-05-19T05:56:24.020Z"
}


For incident data (when collected):

json{
"startPoint": {"latitude": -27.4698, "longitude": 153.0251},
"endPoint": {"latitude": -27.4695, "longitude": 153.0249},
"accelerometerData": [
{"x": 0, "y": 9, "z": 1, "timestamp": 1715056787000},
{"x": 1, "y": 8, "z": 2, "timestamp": 1715056788000}
],
"timestamp": "1715056787000",
"source": "wear_os"
}


What's Excluded

Customer ID and database-specific fields: These will be added by our main app and backend
Extensive UI screens: Focus is on the background service functionality
Authentication: Handled by our main app

Development Resources

What We'll Provide:

Demo project with:

- Stubbed WearIntegration interface
- HealthData and IncidentData class definitions
- Test harness for both phone and watch
- Buttons to trigger continuous sync and incident recording


Backend API documentation

- Staging credentials for testing

What You'll Need

- Android development environment
- At least one physical Wear OS device for testing (not just emulators)
- Google Play Services (for the Wear Data Layer API)

Required Skills & Experience

- Android native development (Kotlin)
- Demonstrated experience with Wear OS development - must have shipped or contributed to at least one Wear OS app or integration
- Background services implementation
- Sensor API expertise
- Experience with the Wear Data Layer API
- Understanding of battery optimization techniques

Timeline & Milestones

- 1 week for implementation
- Milestone 1: Continuous monitoring (heart rate + steps + battery level)
- Milestone 2: On-demand incident recording functionality
- Final delivery: Complete implementation with documentation and testing

Communication

- Primary communication will be via WhatsApp
- Twice daily progress updates expected (morning and afternoon)
- Demo/test builds to be shared when each milestone is ready for review

Additional Notes

- The finished library will be used in a healthcare context, so reliability is critical
- Battery efficiency is a key consideration for our users
- We plan to support a range of Wear OS devices, not just specific models
- We require the data format to exactly match our existing schema for compatibility with our backend

Note to Applicants: Please include proof of your Wear OS development experience in your proposal, such as links to published apps, GitHub repositories, or detailed descriptions of relevant projects. We require developers who have direct hands-on experience with Wear OS, not just theoretical knowledge.
This project is ideal for developers with strong Android experience who understand the nuances of Wear OS development, sensor management, and efficient communication between watch and phone applications.