Sports Event Management App

I'm looking to develop a comprehensive sports event management app for both iOS and Android platforms. The app should cater to event organizers, players, and sponsors, incorporating advertisement features.

Key Features:
- Create and manage events
- Track participant attendance
- Send push notifications

Ideal skills and experience:
- Mobile app development for iOS and Android
- Experience in event management systems
- Knowledge of ad integration in apps
- Familiarity with push notification services

Please provide examples of similar work done.