Cross-Platform Flutter App Development

I'm looking for an experienced Flutter developer to create a cross-platform app (iOS, Android, Web) with payment integration.

Key requirements:
- Payment integration is essential.
- Experience with user authentication and push notifications is a plus.
- Must ensure a smooth user experience across all platforms.

Ideal skills and experience:
- Proficiency in Flutter and Dart
- Strong background in mobile and web app development
- Experience with payment gateways (e.g., Stripe, PayPal)
- Knowledge of UI/UX design principles

Please share your portfolio and relevant experience.