Cross-Platform Task Management App

I'm looking for an experienced mobile app developer to create a task management application for both iOS and Android platforms. The app will allow users to assign tasks, track progress, and receive due date reminders, all managed through email and password authentication.

Key Features:
- Task assignment among users
- Progress tracking on assigned tasks
- Due date reminders for tasks
- User authentication via email and password

Ideal Skills and Experience:
- Proficiency in developing cross-platform mobile applications
- Strong experience with user authentication systems
- Background in task management app development
- Familiarity with both iOS and Android design guidelines

Please provide relevant portfolio work and estimated timelines. Looking forward to your proposals!