E-commerce Flutter App Enhancement

I'm seeking an experienced Flutter developer to further develop and modify an already built e-commerce app for both iOS and Android platforms.

Key Features:
- Enhance existing Product Catalog
- Improve Shopping Cart functionality
- Integrate additional Payment Gateways

Ideal Skills and Experience:
- Proficiency in Flutter
- Strong background in mobile app development for both iOS and Android
- Experience with e-commerce app functionalities
- Ability to understand and modify existing code

Looking forward to your proposals!