Mobile App and Website Development -- 2

I'm looking for a skilled developer or a team to create a mobile app for both iOS and Android platforms, as well as a complementary website. The app will require user authentication and payment processing functionalities.

Key Requirements:
- Mobile app for iOS and Android
- Website with functionalities to be discussed
- User authentication
- Payment processing

Ideal Skills and Experience:
- Experience in developing cross-platform mobile apps
- Strong background in web development
- Expertise in implementing secure user authentication and payment systems
- Ability to work collaboratively and communicate effectively

Please provide samples of your previous work and an estimated timeline for completion.