Smartwatch apps development

Requirement:
1. Builds two smartwatch apps to get realtime sensor data
2. Integrates smartwatch apps into mobile app

Target watch platform:
Smartwatch 1: Apple Watch
Smartwatch 2: Fitbit Watch

Mobile app technology: Ionic Cordova
* We can provide sample project

Use case scenario:
1. Press start in watch app to connect with mobile app
2. Pass realtime heartbeat rate into mobile app
3. Press stop in watch app to disconnect with mobile app
Reference app: Fiton

Please provide the estimate and lead time for the scope