Web App to Desktop and Android Conversion

I need an experienced developer to convert my web application into both a Windows desktop application and an Android application. The Android app should be a cross-platform solution.

Key Requirements:
- Preserve user authentication and messaging system functionalities
- Cross-platform solution for Android app

Ideal Skills and Experience:
- Proven experience in app development, both desktop and mobile
- Strong knowledge of cross-platform development tools
- Familiarity with implementing secure user authentication
- Experience in developing messaging systems within apps

Please provide examples of similar work done and ensure you have the necessary skills to meet these requirements.