Excel Data Analysis App Development

I need a mobile and desktop application to assist with analyzing data from Excel sheets.

Essential Requirements:
- Cross-platform compatibility (iOS, Android, Windows, macOS)
- User-friendly interface
- Ability to perform various types of data analysis (statistical, financial, predictive)
- Data visualization tools (charts, graphs, dashboards)
- Import/export functionality with Excel

Ideal Skills:
- Proficiency in app development for multiple platforms
- Experience with data analysis and visualization tools
- Strong UI/UX design skills
- Familiarity with Excel and its functionalities

Experience in developing similar applications is a plus. Please provide examples of previous work.