Live Tracking Android App for Safety

I'm looking for an experienced android developer to create an app focused on user safety during travel.

Key Features:
- Emergency Button: A quick-access button for users to alert emergency services or selected contacts.
- Continuous Location Sharing: Real-time tracking of the user's location to ensure safety.
- Periodic Check-in Alerts: Regular updates sent to pre-selected contacts or just the system.

Notifications:
- The app should generate push notifications to alert the user/s of any significant events or changes.

User Authentication:
- The app should require a username and password for user log in. No need for biometric or social media login.

Ideal Skills and Experience:
- Extensive experience in Android app development.
- Previous work with live tracking systems is a plus.
- Understanding of safety protocols and features for travel.
- Skills in creating user-friendly interfaces.

Please provide examples of relevant past work.