Cross-Platform E-Commerce App Development

I'm seeking an experienced mobile app developer to create an e-commerce app for both iOS and Android platforms.

Key Requirements:
- Primary purpose: E-commerce
- Must support both iOS and Android
- Essential functionality: Payment gateway integration

Ideal Skills and Experience:
- Proven experience in developing e-commerce mobile applications
- Expertise in payment gateway integration
- Familiarity with both iOS and Android development
- Strong UI/UX design skills to ensure a user-friendly experience
- Ability to deliver within budget and timeline

Please provide examples of previous work and a brief outline of your approach to this project.