E-Commerce Website and App Development

I'm looking for a professional developer to create a responsive and user-friendly e-commerce website and mobile app. The site and app should have a frontend and backend, with an intuitive backend for easy management.

Requirements:
- Can be built on WordPress, Shopify, or Magento
- Must be responsive and user-friendly
- Frontend and backend development
- User-friendly backend interface
- Must be registered on Play Store
- Support for both physical and digital products

Ideal Skills and Experience:
- Proven experience in developing e-commerce platforms
- Strong knowledge of WordPress, Shopify, and Magento
- Expertise in app development and Play Store registration
- Background in UI/UX design for optimal user experience
- Ability to deliver within budget and timeline

Please provide examples of previous work and a detailed proposal.