Prompts for creating a professional Android/iOS app

"Act as a senior mobile app product manager. I need a detailed app concept for a new mobile app designed for freelance graphic designers. The app's primary function is to help them organize their projects and track billable hours. The app must have a clean, minimalist UI, and it should function seamlessly offline. Please provide the following:

1.       A detailed user persona for a target user.

2.       The app's main features and their purpose.

3.       A wireframe-style description of 5 key screens.

4.       A list of potential challenges to consider during development (e.g., data sync, security)."