Cross-Platform Productivity App Development

I'm seeking a seasoned mobile app developer to create a feature-rich productivity app for both iOS and Android.

Key Features:
- Task Management: The app should enable users to create, assign, and track tasks.
- Calendar Integration: Seamless sync with popular calendar platforms is a must.
- Note Taking: A built-in, user-friendly note-taking function should be included.
- Chat: The app should have a secure, real-time chat feature.
- Bill Split: Users should be able to split bills effortlessly.
- Shared Bills: A function to manage and track shared bills over time.

Ideal Skills and Experience:
- Proficiency in cross-platform mobile app development (KMP preferred)
- Prior experience with developing productivity tools will be highly regarded.
- Strong knowledge in implementing chat features in apps
- Expertise in task management and calendar integration functionalities
- Familiarity with bill splitting features in apps

I am looking for a professional who can deliver a high-quality, user-friendly app that meets these specifications.