Multi-Platform App Development

I need an experienced app developer to create a multi-platform application.

Key Requirements:
- Experience in developing mobile and web apps
- Proficiency in both iOS and Android platforms
- Strong background in e-commerce, social networking, or productivity tool apps
- Ability to design a user-friendly interface and ensure seamless functionality

Ideal Skills:
- Mobile app development (Swift, Kotlin, React Native)
- Web app development (JavaScript, HTML, CSS)
- UI/UX design
- Experience with backend services (Node.js, Firebase, etc.)
- Strong problem-solving skills and attention to detail

Please provide a portfolio showcasing similar projects.