Android Developer for React Native Sensor Module

I’m building a mobile app using React Native, and I need an experienced Android developer to implement a native module that handles background processing and sensor-based event detection.

Scope of work:

1. Build a native Android foreground service that:
- Runs reliably in the background
- Is not killed by the OS (handle Doze mode, battery optimization)

2. Detect the following signals:
- Screen ON/OFF state
- Charging state (plug/unplug)
- Basic motion detection using accelerometer (low-frequency sampling)
- Optional: ambient light sensor (if available)

3. Implement logic to:
- Track inactivity (e.g., screen off + no interaction)
- Combine signals and trigger an event when conditions are met
- Ensure low battery usage (no continuous high-frequency polling)

4. Alarm functionality:
- Schedule exact alarms using AlarmManager
- Ensure alarms work even in Doze mode

5. React Native bridge:
- Expose native functionality to React Native via a clean module interface
- Send events from native → JS when detection happens

Requirements:
- Strong experience with Android (Kotlin preferred)
- Experience with foreground services and background execution limits
- Familiarity with sensors (SensorManager)
- Experience handling Doze mode and battery optimization
- Experience creating React Native native modules

Deliverables:
- Clean, well-structured Android code
- Documentation on how to use the native module from React Native
- Basic demo showing detection + alarm trigger working

Please include:
- Examples of similar work (background services, sensors, or system-level apps)
- Brief explanation of how you would prevent the app from being killed

We will start with a small paid test task before proceeding to full project.