Cross-Platform Weather Alert App

I need a mobile app developed for both iOS and Android platforms that sends push notifications with custom sounds to alert users about weather emergencies.

The app should trigger alerts for the following weather emergencies:
- Hurricanes
- Tornadoes
- Floods
- Severe Thunderstorms

Notifications should be based on:
- Advisories
- Watches
- Warnings
- Emergency Alerts
- PTA (Potential Threat Alerts)

Key Requirements:
- Cross-platform compatibility (iOS and Android)
- Custom sound for notifications
- Timely and reliable push notifications

Ideal Skills & Experience:
- Mobile app development (iOS & Android)
- Experience with push notification systems
- Knowledge of weather alert APIs
- UI/UX design for mobile applications
- Background in emergency alert systems is a plus

Please include examples of similar work in your bids.