Multiplatform Rummy Game App Development

I am looking for a talented app developer who can create a rummy game application for iOS and Android with specific features and functionalities.

Key Features:
- Online multiplayer: Players should be able to play with each other in real-time, creating a competitive and engaging environment.
- In-app purchases: There should be options for players to make in-app purchases, enhancing their gameplay experience.
- Varied themes: I'd like the game to have multiple themes to suit different player preferences.

Specific Functionalities:
- User registration and login: A secure registration and login system is needed for players to create accounts and access the game.
- Private tables: I want to include a feature where users can create private tables and invite specific players to join the game.

Ideal skills and experience:
- Experience in developing multiplayer games is a big plus.
- Proficient in cross-platform development with a focus on iOS and Android.
- Familiarity with in-app purchase integration.
- Strong background in creating user account systems and invitation functionalities.
- Prior work on card game applications or similar projects is highly desirable.