Utility Mobile App Development

I'm looking for a skilled mobile app developer to create a utility-focused app that supports both iOS and Android platforms.

Key Features:
- User Authentication: The app needs a secure and efficient user authentication system.
- Push Notifications: I want the app to keep users engaged with timely push notifications.
- Offline Functionality: Given the nature of utility apps, this one should offer offline functionality as well.

Ideal Skills:
- Proficiency in cross-platform mobile app development
- Experience with user authentication systems
- Knowledge of implementing push notifications
- Ability to create apps with offline functionality

Please provide examples of previous similar projects you've worked on.